diff --git a/bashunit b/bashunit
index 52c49b05..cf71d475 100755
--- a/bashunit
+++ b/bashunit
@@ -91,7 +91,7 @@ source "$BASHUNIT_ROOT_DIR/src/runner/index.sh"
 source "$BASHUNIT_ROOT_DIR/src/benchmark.sh"
 source "$BASHUNIT_ROOT_DIR/src/bashunit.sh"
 source "$BASHUNIT_ROOT_DIR/src/init.sh"
-source "$BASHUNIT_ROOT_DIR/src/learn.sh"
+source "$BASHUNIT_ROOT_DIR/src/learn/index.sh"
 source "$BASHUNIT_ROOT_DIR/src/main.sh"
 
 bashunit::check_os::init
diff --git a/src/learn.sh b/src/learn.sh
deleted file mode 100644
index d9bb6251..00000000
--- a/src/learn.sh
+++ /dev/null
@@ -1,1213 +0,0 @@
-#!/usr/bin/env bash
-# shellcheck disable=SC2016
-
-##
-# Interactive learning module for bashunit
-# Provides guided tutorials and exercises to learn bashunit
-##
-
-LEARN_TEMP_DIR=""
-declare -r LEARN_PROGRESS_FILE="$HOME/.bashunit_learn_progress"
-
-##
-# Initialize learning environment
-##
-function bashunit::learn::init() {
-  LEARN_TEMP_DIR=$("${MKTEMP:-mktemp}" -d "${TMPDIR:-/tmp}/bashunit_learn.XXXXXXXX")
-  mkdir -p tests
-}
-
-##
-# Cleanup learning environment
-##
-function bashunit::learn::cleanup() {
-  if [ -n "${LEARN_TEMP_DIR:-}" ] && [ -d "$LEARN_TEMP_DIR" ]; then
-    rm -rf "$LEARN_TEMP_DIR"
-  fi
-}
-
-##
-# Print the learning menu
-##
-function bashunit::learn::print_menu() {
-  cat <<EOF
-${_BASHUNIT_COLOR_BOLD}${_BASHUNIT_COLOR_PASSED}bashunit${_BASHUNIT_COLOR_DEFAULT} - Interactive Learning
-
-Choose a lesson:
-
-  ${_BASHUNIT_COLOR_BOLD}1.${_BASHUNIT_COLOR_DEFAULT} Basics - Your First Test
-  ${_BASHUNIT_COLOR_BOLD}2.${_BASHUNIT_COLOR_DEFAULT} Assertions - Testing Different Conditions
-  ${_BASHUNIT_COLOR_BOLD}3.${_BASHUNIT_COLOR_DEFAULT} Setup & Teardown - Managing Test Lifecycle
-  ${_BASHUNIT_COLOR_BOLD}4.${_BASHUNIT_COLOR_DEFAULT} Testing Functions - Unit Testing Patterns
-  ${_BASHUNIT_COLOR_BOLD}5.${_BASHUNIT_COLOR_DEFAULT} Testing Scripts - Integration Testing
-  ${_BASHUNIT_COLOR_BOLD}6.${_BASHUNIT_COLOR_DEFAULT} Mocking - Test Doubles and Mocks
-  ${_BASHUNIT_COLOR_BOLD}7.${_BASHUNIT_COLOR_DEFAULT} Spies - Verifying Function Calls
-  ${_BASHUNIT_COLOR_BOLD}8.${_BASHUNIT_COLOR_DEFAULT} Data Providers - Parameterized Tests
-  ${_BASHUNIT_COLOR_BOLD}9.${_BASHUNIT_COLOR_DEFAULT} Exit Codes - Testing Success and Failure
-  ${_BASHUNIT_COLOR_BOLD}10.${_BASHUNIT_COLOR_DEFAULT} Complete Challenge - Real World Scenario
-
-  ${_BASHUNIT_COLOR_BOLD}p.${_BASHUNIT_COLOR_DEFAULT} Show Progress
-  ${_BASHUNIT_COLOR_BOLD}r.${_BASHUNIT_COLOR_DEFAULT} Reset Progress
-  ${_BASHUNIT_COLOR_BOLD}q.${_BASHUNIT_COLOR_DEFAULT} Quit
-
-Enter your choice:
-EOF
-}
-
-##
-# Main learning loop
-##
-function bashunit::learn::start() {
-  bashunit::learn::init
-
-  trap 'bashunit::learn::cleanup' EXIT
-
-  while true; do
-    echo ""
-    bashunit::learn::print_menu
-    read -r choice
-    echo ""
-
-    case "$choice" in
-    1) bashunit::learn::lesson_basics || true ;;
-    2) bashunit::learn::lesson_assertions || true ;;
-    3) bashunit::learn::lesson_lifecycle || true ;;
-    4) bashunit::learn::lesson_functions || true ;;
-    5) bashunit::learn::lesson_scripts || true ;;
-    6) bashunit::learn::lesson_mocking || true ;;
-    7) bashunit::learn::lesson_spies || true ;;
-    8) bashunit::learn::lesson_data_providers || true ;;
-    9) bashunit::learn::lesson_exit_codes || true ;;
-    10) bashunit::learn::lesson_challenge || true ;;
-    p) bashunit::learn::show_progress ;;
-    r) bashunit::learn::reset_progress ;;
-    q)
-      echo "${_BASHUNIT_COLOR_PASSED}Happy testing!${_BASHUNIT_COLOR_DEFAULT}"
-      break
-      ;;
-    *)
-      echo "${_BASHUNIT_COLOR_FAILED}Invalid choice. Please try again.${_BASHUNIT_COLOR_DEFAULT}"
-      ;;
-    esac
-  done
-
-  bashunit::learn::cleanup
-}
-
-##
-# Mark lesson as completed
-##
-function bashunit::learn::mark_completed() {
-  local lesson=$1
-  echo "$lesson" >>"$LEARN_PROGRESS_FILE"
-}
-
-##
-# Check if lesson is completed
-##
-function bashunit::learn::is_completed() {
-  local lesson=$1
-  [ -f "$LEARN_PROGRESS_FILE" ] && [ "$("$GREP" -c "^$lesson$" "$LEARN_PROGRESS_FILE" || true)" -gt 0 ]
-}
-
-##
-# Show learning progress
-##
-function bashunit::learn::show_progress() {
-  if [ ! -f "$LEARN_PROGRESS_FILE" ]; then
-    echo "${_BASHUNIT_COLOR_INCOMPLETE}No progress yet. Start with lesson 1!${_BASHUNIT_COLOR_DEFAULT}"
-    return
-  fi
-
-  echo "${_BASHUNIT_COLOR_BOLD}Your Progress:${_BASHUNIT_COLOR_DEFAULT}"
-  echo ""
-
-  local total_lessons=10
-  local completed=0
-
-  local i
-  for i in $(seq 1 $total_lessons); do
-    if bashunit::learn::is_completed "lesson_$i"; then
-      echo "  ${_BASHUNIT_COLOR_PASSED}✓${_BASHUNIT_COLOR_DEFAULT} Lesson $i completed"
-      ((++completed)) || true
-    else
-      echo "  ${_BASHUNIT_COLOR_INCOMPLETE}○${_BASHUNIT_COLOR_DEFAULT} Lesson $i"
-    fi
-  done
-
-  echo ""
-  echo "Progress: $completed/$total_lessons lessons completed"
-
-  if [ $completed -eq $total_lessons ]; then
-    echo ""
-    printf "%s%s🎉 Congratulations! You've completed all lessons!%s\n" \
-      "$_BASHUNIT_COLOR_PASSED" "$_BASHUNIT_COLOR_BOLD" "$_BASHUNIT_COLOR_DEFAULT"
-  fi
-
-  read -p "Press Enter to continue..." -r
-}
-
-##
-# Reset learning progress
-##
-function bashunit::learn::reset_progress() {
-  rm -f "$LEARN_PROGRESS_FILE"
-  echo "${_BASHUNIT_COLOR_PASSED}Progress reset successfully.${_BASHUNIT_COLOR_DEFAULT}"
-  read -p "Press Enter to continue..." -r
-}
-
-##
-# Create the example file automatically
-# Arguments: $1 - filename, $2 - file content
-##
-function bashunit::learn::create_example_file() {
-  local filename=$1
-  local content=$2
-
-  echo ""
-  echo "Creating example file ${_BASHUNIT_COLOR_BOLD}$filename${_BASHUNIT_COLOR_DEFAULT}..."
-  echo "$content" >"$filename"
-  chmod +x "$filename"
-  echo "${_BASHUNIT_COLOR_PASSED}✓ Created $filename${_BASHUNIT_COLOR_DEFAULT}"
-  echo ""
-  echo "File created! Edit it to complete the TODO items, then run this lesson again."
-  read -p "Press Enter to continue..." -r
-  return 0
-}
-
-##
-# Run a lesson test and check results
-##
-function bashunit::learn::run_lesson_test() {
-  local test_file=$1
-  local lesson_number=$2
-
-  echo "${_BASHUNIT_COLOR_BOLD}Running your test...${_BASHUNIT_COLOR_DEFAULT}"
-  echo ""
-
-  if "$BASHUNIT_ROOT_DIR/bashunit" "$test_file" --simple; then
-    echo ""
-    printf "%s%s✓ Excellent! Lesson %s completed!%s\n" \
-      "$_BASHUNIT_COLOR_PASSED" "$_BASHUNIT_COLOR_BOLD" "$lesson_number" "$_BASHUNIT_COLOR_DEFAULT"
-    bashunit::learn::mark_completed "lesson_$lesson_number"
-    read -p "Press Enter to continue..." -r
-    return 0
-  else
-    echo ""
-    echo "${_BASHUNIT_COLOR_FAILED}Not quite right. Review the requirements and try again.${_BASHUNIT_COLOR_DEFAULT}"
-    read -p "Press Enter to continue..." -r
-    return 1
-  fi
-}
-
-##
-# Lesson 1: Basics - Your First Test
-##
-function bashunit::learn::lesson_basics() {
-  clear
-  cat <<'EOF'
-╔════════════════════════════════════════════════════════════════╗
-║                    Lesson 1: Your First Test                   ║
-╚════════════════════════════════════════════════════════════════╝
-
-Welcome to bashunit! Let's write your first test.
-
-CONCEPT: A test is a function that starts with 'test_' and uses
-assertions to verify behavior.
-
-TASK: Create a test file that checks if two values are equal.
-
-File: tests/first_test.sh
-───────────────────────────────────────────────────────────────
-#!/usr/bin/env bash
-
-function test_bashunit_works() {
-  # TODO: Use assert_same to check if "hello" equals "hello"
-  # Hint: assert_same "expected" "actual"
-}
-───────────────────────────────────────────────────────────────
-
-TIPS:
-  • The assert_same function takes two arguments:
-    assert_same "expected" "actual"
-  • Test functions must start with "test_" prefix
-  • Always quote your strings to avoid word splitting
-  • Keep test files in a tests/ directory for better organization
-EOF
-
-  local default_file="tests/first_test.sh"
-  echo ""
-  printf "When ready, enter file path %s[%s]%s: " \
-    "${_BASHUNIT_COLOR_FAINT}" "$default_file" "${_BASHUNIT_COLOR_DEFAULT}"
-  read -r test_file
-  test_file="${test_file:-$default_file}"
-
-  if [ ! -f "$test_file" ]; then
-    local template='#!/usr/bin/env bash
-
-function test_bashunit_works() {
-  # TODO: Use assert_same to check if "hello" equals "hello"
-  # Hint: assert_same "expected" "actual"
-}'
-
-    bashunit::learn::create_example_file "$test_file" "$template"
-    return 1
-  fi
-
-  # Check if file contains assert_same
-  if [ "$("$GREP" -c "assert_same" "$test_file" || true)" -eq 0 ]; then
-    echo "${_BASHUNIT_COLOR_FAILED}Your test should use assert_same${_BASHUNIT_COLOR_DEFAULT}"
-    read -p "Press Enter to continue..." -r
-    return 1
-  fi
-
-  bashunit::learn::run_lesson_test "$test_file" 1
-}
-
-##
-# Lesson 2: Assertions - Testing Different Conditions
-##
-function bashunit::learn::lesson_assertions() {
-  clear
-  cat <<'EOF'
-╔════════════════════════════════════════════════════════════════╗
-║              Lesson 2: Testing Different Conditions            ║
-╚════════════════════════════════════════════════════════════════╝
-
-CONCEPT: bashunit provides many assertion functions for different checks:
-  • assert_same - exact equality
-  • assert_contains - substring check
-  • assert_matches - regex pattern
-  • assert_not_same - inequality
-  • assert_empty - checks if value is empty
-  • assert_not_empty - checks if value is not empty
-
-TASK: Write a test file with 3 different assertions.
-
-File: tests/assertions_test.sh
-───────────────────────────────────────────────────────────────
-#!/usr/bin/env bash
-
-function test_multiple_assertions() {
-  local message="Hello, bashunit!"
-
-  # TODO: Check that message contains "bashunit"
-  # Hint: assert_contains "substring" "$message"
-
-  # TODO: Check that message matches the pattern "Hello.*!"
-  # Hint: assert_matches "pattern" "$message"
-
-  # TODO: Check that message is not empty
-  # Hint: assert_not_empty "$message"
-}
-───────────────────────────────────────────────────────────────
-
-TIPS:
-  • assert_same checks exact equality (useful for strings/numbers)
-  • assert_contains is more flexible for partial matches
-  • assert_matches uses regex patterns (e.g., "^[0-9]+$" for numbers)
-  • Explore more: assert_empty, assert_true, assert_false
-EOF
-
-  local default_file="tests/assertions_test.sh"
-  echo ""
-  printf "When ready, enter file path %s[%s]%s: " \
-    "${_BASHUNIT_COLOR_FAINT}" "$default_file" "${_BASHUNIT_COLOR_DEFAULT}"
-  read -r test_file
-  test_file="${test_file:-$default_file}"
-
-  if [ ! -f "$test_file" ]; then
-    local template='#!/usr/bin/env bash
-
-function test_multiple_assertions() {
-  local message="Hello, bashunit!"
-
-  # TODO: Check that message contains "bashunit"
-  # Hint: assert_contains "substring" "$message"
-
-  # TODO: Check that message matches the pattern "Hello.*!"
-  # Hint: assert_matches "pattern" "$message"
-
-  # TODO: Check that message is not empty
-  # Hint: assert_not_empty "$message"
-}'
-
-    bashunit::learn::create_example_file "$test_file" "$template"
-    return 1
-  fi
-
-  if [ "$("$GREP" -c "assert_contains" "$test_file" || true)" -eq 0 ] ||
-    [ "$("$GREP" -c "assert_matches" "$test_file" || true)" -eq 0 ] ||
-    [ "$("$GREP" -c "assert_not_empty" "$test_file" || true)" -eq 0 ]; then
-    echo "${_BASHUNIT_COLOR_FAILED}Your test should use all three assertion types${_BASHUNIT_COLOR_DEFAULT}"
-    read -p "Press Enter to continue..." -r
-    return 1
-  fi
-
-  bashunit::learn::run_lesson_test "$test_file" 2
-}
-
-##
-# Lesson 3: Setup & Teardown - Managing Test Lifecycle
-##
-function bashunit::learn::lesson_lifecycle() {
-  clear
-  cat <<'EOF'
-╔════════════════════════════════════════════════════════════════╗
-║           Lesson 3: Setup and Teardown Functions               ║
-╚════════════════════════════════════════════════════════════════╝
-
-CONCEPT: Tests often need preparation and cleanup. bashunit provides:
-  • set_up() - runs before EACH test
-  • tear_down() - runs after EACH test
-  • set_up_before_script() - runs once before ALL tests
-  • tear_down_after_script() - runs once after ALL tests
-
-TASK: Create a test that uses setup and teardown to manage files.
-
-File: tests/lifecycle_test.sh
-───────────────────────────────────────────────────────────────
-#!/usr/bin/env bash
-
-function set_up() {
-  # Create a temp file before each test
-  # TODO: export TEST_FILE="/tmp/test_$$"
-  # TODO: echo "test content" > "$TEST_FILE"
-}
-
-function tear_down() {
-  # Clean up after each test
-  # TODO: rm -f "$TEST_FILE"
-}
-
-function test_file_exists() {
-  # TODO: assert_file_exists "$TEST_FILE"
-}
-
-function test_file_has_content() {
-  # TODO: assert_file_contains "test content" "$TEST_FILE"
-}
-───────────────────────────────────────────────────────────────
-
-TIPS:
-  • set_up() runs before EACH test (good for test isolation)
-  • set_up_before_script() runs ONCE before all tests (good for expensive setup)
-  • Always clean up in tear_down() to avoid polluting other tests
-  • Use $$ for unique temp file names to avoid conflicts
-EOF
-
-  local default_file="tests/lifecycle_test.sh"
-  echo ""
-  printf "When ready, enter file path %s[%s]%s: " \
-    "${_BASHUNIT_COLOR_FAINT}" "$default_file" "${_BASHUNIT_COLOR_DEFAULT}"
-  read -r test_file
-  test_file="${test_file:-$default_file}"
-
-  if [ ! -f "$test_file" ]; then
-    local template='#!/usr/bin/env bash
-
-function set_up() {
-  # Create a temp file before each test
-  # TODO: export TEST_FILE="/tmp/test_$$"
-  # TODO: echo "test content" > "$TEST_FILE"
-}
-
-function tear_down() {
-  # Clean up after each test
-  # TODO: rm -f "$TEST_FILE"
-}
-
-function test_file_exists() {
-  # TODO: assert_file_exists "$TEST_FILE"
-}
-
-function test_file_has_content() {
-  # TODO: assert_file_contains "test content" "$TEST_FILE"
-}'
-
-    bashunit::learn::create_example_file "$test_file" "$template"
-    return 1
-  fi
-
-  if [ "$("$GREP" -c "function set_up()" "$test_file" || true)" -eq 0 ] ||
-    [ "$("$GREP" -c "function tear_down()" "$test_file" || true)" -eq 0 ]; then
-    echo "${_BASHUNIT_COLOR_FAILED}Your test should define set_up and tear_down functions${_BASHUNIT_COLOR_DEFAULT}"
-    read -p "Press Enter to continue..." -r
-    return 1
-  fi
-
-  bashunit::learn::run_lesson_test "$test_file" 3
-}
-
-##
-# Lesson 4: Testing Functions
-##
-function bashunit::learn::lesson_functions() {
-  clear
-  cat <<'EOF'
-╔════════════════════════════════════════════════════════════════╗
-║              Lesson 4: Testing Bash Functions                  ║
-╚════════════════════════════════════════════════════════════════╝
-
-CONCEPT: To test functions, source the file containing them, then
-call them in your tests.
-
-TASK: Create a script with a function, then test it.
-
-File: calculator.sh (source code)
-───────────────────────────────────────────────────────────────
-#!/usr/bin/env bash
-
-function add() {
-  echo $(($1 + $2))
-}
-───────────────────────────────────────────────────────────────
-
-File: tests/calculator_test.sh (test file)
-───────────────────────────────────────────────────────────────
-#!/usr/bin/env bash
-
-function set_up() {
-  # TODO: Source calculator.sh from parent directory
-  # Hint: source ../calculator.sh
-}
-
-function test_add_positive_numbers() {
-  # TODO: Test that add 2 3 returns "5"
-  # Hint: result=$(add 2 3)
-  # Hint: assert_same "5" "$result"
-}
-
-function test_add_negative_numbers() {
-  # TODO: Test that add -2 -3 returns "-5"
-  # Hint: result=$(add -2 -3)
-  # Hint: assert_same "-5" "$result"
-}
-───────────────────────────────────────────────────────────────
-
-TIPS:
-  • Source files in set_up() to reload them fresh for each test
-  • Capture function output with: result=$(function_name args)
-  • Test edge cases: positive, negative, zero, large numbers
-  • Source files from parent directory: source ../file.sh
-EOF
-
-  local default_file="tests/calculator_test.sh"
-  echo ""
-  printf "When ready, enter TEST file path %s[%s]%s: " \
-    "${_BASHUNIT_COLOR_FAINT}" "$default_file" "${_BASHUNIT_COLOR_DEFAULT}"
-  read -r test_file
-  test_file="${test_file:-$default_file}"
-
-  if [ ! -f "$test_file" ]; then
-    local template='#!/usr/bin/env bash
-
-function set_up() {
-  # TODO: Source calculator.sh from parent directory
-  # Hint: source ../calculator.sh
-}
-
-function test_add_positive_numbers() {
-  # TODO: Test that add 2 3 returns "5"
-  # Hint: result=$(add 2 3)
-  # Hint: assert_same "5" "$result"
-}
-
-function test_add_negative_numbers() {
-  # TODO: Test that add -2 -3 returns "-5"
-  # Hint: result=$(add -2 -3)
-  # Hint: assert_same "-5" "$result"
-}'
-
-    bashunit::learn::create_example_file "$test_file" "$template"
-    return 1
-  fi
-
-  if [ "$("$GREP" -c "source" "$test_file" || true)" -eq 0 ]; then
-    echo "${_BASHUNIT_COLOR_FAILED}Your test should source the calculator.sh file${_BASHUNIT_COLOR_DEFAULT}"
-    read -p "Press Enter to continue..." -r
-    return 1
-  fi
-
-  bashunit::learn::run_lesson_test "$test_file" 4
-}
-
-##
-# Lesson 5: Testing Scripts
-##
-function bashunit::learn::lesson_scripts() {
-  clear
-  cat <<'EOF'
-╔════════════════════════════════════════════════════════════════╗
-║                 Lesson 5: Testing Bash Scripts                 ║
-╚════════════════════════════════════════════════════════════════╝
-
-CONCEPT: Scripts that execute commands directly are tested differently.
-Run them and capture their output.
-
-TASK: Create a script and test its output.
-
-File: greeter.sh (source code)
-───────────────────────────────────────────────────────────────
-#!/usr/bin/env bash
-name=${1:-World}
-echo "Hello, $name!"
-───────────────────────────────────────────────────────────────
-
-File: tests/greeter_test.sh (test file)
-───────────────────────────────────────────────────────────────
-#!/usr/bin/env bash
-
-function test_default_greeting() {
-  # TODO: Run greeter.sh from parent directory and capture output
-  # Hint: output=$(../greeter.sh)
-
-  # TODO: Assert output contains "Hello, World!"
-  # Hint: assert_contains "Hello, World!" "$output"
-}
-
-function test_custom_greeting() {
-  # TODO: Run greeter.sh with argument "Alice"
-  # Hint: output=$(../greeter.sh "Alice")
-
-  # TODO: Assert output contains "Hello, Alice!"
-  # Hint: assert_contains "Hello, Alice!" "$output"
-}
-───────────────────────────────────────────────────────────────
-
-TIPS:
-  • Use command substitution: output=$(./script.sh)
-  • Make scripts executable: chmod +x script.sh
-  • Test both default behavior and with various arguments
-  • Scripts run in subshells, so they can't modify parent environment
-  • Run scripts from parent directory: ../script.sh
-EOF
-
-  local default_file="tests/greeter_test.sh"
-  echo ""
-  printf "When ready, enter TEST file path %s[%s]%s: " \
-    "${_BASHUNIT_COLOR_FAINT}" "$default_file" "${_BASHUNIT_COLOR_DEFAULT}"
-  read -r test_file
-  test_file="${test_file:-$default_file}"
-
-  if [ ! -f "$test_file" ]; then
-    local template='#!/usr/bin/env bash
-
-function test_default_greeting() {
-  # TODO: Run greeter.sh from parent directory and capture output
-  # Hint: output=$(../greeter.sh)
-
-  # TODO: Assert output contains "Hello, World!"
-  # Hint: assert_contains "Hello, World!" "$output"
-}
-
-function test_custom_greeting() {
-  # TODO: Run greeter.sh with argument "Alice"
-  # Hint: output=$(../greeter.sh "Alice")
-
-  # TODO: Assert output contains "Hello, Alice!"
-  # Hint: assert_contains "Hello, Alice!" "$output"
-}'
-
-    bashunit::learn::create_example_file "$test_file" "$template"
-    return 1
-  fi
-
-  bashunit::learn::run_lesson_test "$test_file" 5
-}
-
-##
-# Lesson 6: Mocking
-##
-function bashunit::learn::lesson_mocking() {
-  clear
-  cat <<'EOF'
-╔════════════════════════════════════════════════════════════════╗
-║               Lesson 6: Mocking External Commands              ║
-╚════════════════════════════════════════════════════════════════╝
-
-CONCEPT: Mocks let you override external commands or functions to
-control their behavior in tests.
-
-TASK: Test a function that uses external commands.
-
-File: system_info.sh (source code)
-───────────────────────────────────────────────────────────────
-#!/usr/bin/env bash
-
-function get_system_info() {
-  echo "OS: $(uname -s)"
-}
-───────────────────────────────────────────────────────────────
-
-File: tests/system_info_test.sh (test file)
-───────────────────────────────────────────────────────────────
-#!/usr/bin/env bash
-
-function set_up() {
-  source ../system_info.sh
-}
-
-function test_system_info_on_linux() {
-  # TODO: Mock uname to return "Linux"
-  # Hint: mock uname echo "Linux"
-
-  local output
-  output=$(get_system_info)
-
-  # TODO: Assert output contains "OS: Linux"
-}
-
-function test_system_info_on_macos() {
-  # TODO: Mock uname to return "Darwin"
-
-  local output
-  output=$(get_system_info)
-
-  # TODO: Assert output contains "OS: Darwin"
-}
-───────────────────────────────────────────────────────────────
-
-TIPS:
-  • Mocks replace commands/functions with custom behavior
-  • Syntax: mock command_name echo "mocked output"
-  • Mocks are automatically cleaned up after each test
-  • Use mocks to avoid calling expensive external commands
-EOF
-
-  local default_file="tests/system_info_test.sh"
-  echo ""
-  printf "When ready, enter TEST file path %s[%s]%s: " \
-    "${_BASHUNIT_COLOR_FAINT}" "$default_file" "${_BASHUNIT_COLOR_DEFAULT}"
-  read -r test_file
-  test_file="${test_file:-$default_file}"
-
-  if [ ! -f "$test_file" ]; then
-    local template='#!/usr/bin/env bash
-
-function set_up() {
-  source ../system_info.sh
-}
-
-function test_system_info_on_linux() {
-  # TODO: Mock uname to return "Linux"
-  # Hint: mock uname echo "Linux"
-
-  local output
-  output=$(get_system_info)
-
-  # TODO: Assert output contains "OS: Linux"
-}
-
-function test_system_info_on_macos() {
-  # TODO: Mock uname to return "Darwin"
-
-  local output
-  output=$(get_system_info)
-
-  # TODO: Assert output contains "OS: Darwin"
-}'
-
-    bashunit::learn::create_example_file "$test_file" "$template"
-    return 1
-  fi
-
-  if [ "$("$GREP" -c "mock" "$test_file" || true)" -eq 0 ]; then
-    echo "${_BASHUNIT_COLOR_FAILED}Your test should use mock${_BASHUNIT_COLOR_DEFAULT}"
-    read -p "Press Enter to continue..." -r
-    return 1
-  fi
-
-  bashunit::learn::run_lesson_test "$test_file" 6
-}
-
-##
-# Lesson 7: Spies
-##
-function bashunit::learn::lesson_spies() {
-  clear
-  cat <<'EOF'
-╔════════════════════════════════════════════════════════════════╗
-║              Lesson 7: Spies - Verifying Calls                 ║
-╚════════════════════════════════════════════════════════════════╝
-
-CONCEPT: Spies let you verify that functions were called with specific
-arguments or a certain number of times.
-
-KEY DIFFERENCE: Spies track calls without changing behavior, while
-mocks (Lesson 6) replace the function entirely with custom behavior.
-
-TASK: Use spies to verify function calls.
-
-File: deploy.sh
-───────────────────────────────────────────────────────────────
-#!/usr/bin/env bash
-
-function deploy_app() {
-  git push origin main
-  docker build -t myapp .
-  docker push myapp
-}
-───────────────────────────────────────────────────────────────
-
-File: deploy_test.sh
-───────────────────────────────────────────────────────────────
-#!/usr/bin/env bash
-
-function set_up() {
-  source deploy.sh
-}
-
-function test_deploy_calls_git_push() {
-  # TODO: Create spies for git and docker
-  # Hint: spy git
-  # Hint: spy docker
-
-  deploy_app
-
-  # TODO: Assert git was called
-  # Hint: assert_have_been_called git
-
-  # TODO: Assert docker was called
-}
-
-function test_deploy_calls_docker_twice() {
-  # TODO: Spy on docker
-
-  deploy_app
-
-  # TODO: Assert docker was called exactly 2 times
-  # Hint: assert_have_been_called_times 2 docker
-}
-───────────────────────────────────────────────────────────────
-
-TIPS:
-  • Spies track calls but don't change behavior (unlike mocks)
-  • assert_have_been_called - verifies at least one call
-  • assert_have_been_called_times N - verifies exact call count
-  • assert_have_been_called_with - verifies specific arguments
-  • Spies are cleaned up automatically after each test
-EOF
-
-  local default_file="deploy_test.sh"
-  echo ""
-  printf "When ready, enter TEST file path %s[%s]%s: " \
-    "${_BASHUNIT_COLOR_FAINT}" "$default_file" "${_BASHUNIT_COLOR_DEFAULT}"
-  read -r test_file
-  test_file="${test_file:-$default_file}"
-
-  if [ ! -f "$test_file" ]; then
-    local template='#!/usr/bin/env bash
-
-function set_up() {
-  source deploy.sh
-}
-
-function test_deploy_calls_git_push() {
-  # TODO: Create spies for git and docker
-  # Hint: spy git
-  # Hint: spy docker
-
-  deploy_app
-
-  # TODO: Assert git was called
-  # Hint: assert_have_been_called git
-
-  # TODO: Assert docker was called
-}
-
-function test_deploy_calls_docker_twice() {
-  # TODO: Spy on docker
-
-  deploy_app
-
-  # TODO: Assert docker was called exactly 2 times
-  # Hint: assert_have_been_called_times 2 docker
-}'
-
-    bashunit::learn::create_example_file "$test_file" "$template"
-    return 1
-  fi
-
-  if [ "$("$GREP" -c "spy" "$test_file" || true)" -eq 0 ]; then
-    echo "${_BASHUNIT_COLOR_FAILED}Your test should use spy${_BASHUNIT_COLOR_DEFAULT}"
-    read -p "Press Enter to continue..." -r
-    return 1
-  fi
-
-  bashunit::learn::run_lesson_test "$test_file" 7
-}
-
-##
-# Lesson 8: Data Providers
-##
-function bashunit::learn::lesson_data_providers() {
-  clear
-  cat <<'EOF'
-╔════════════════════════════════════════════════════════════════╗
-║           Lesson 8: Data Providers - Parameterized Tests       ║
-╚════════════════════════════════════════════════════════════════╝
-
-CONCEPT: Data providers let you run the same test with different inputs.
-Define a function that echoes test data, one per line.
-
-HOW IT WORKS: Each line from data_provider_* becomes $1 in your test.
-The test runs once for each line of data.
-
-TASK: Test multiple email formats using a data provider.
-
-File: validator.sh
-───────────────────────────────────────────────────────────────
-#!/usr/bin/env bash
-
-function is_valid_email() {
-  local email_pattern='^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$'
-  [ "$(echo "$1" | "$GREP" -cE "$email_pattern" || true)" -gt 0 ]
-}
-───────────────────────────────────────────────────────────────
-
-File: validator_test.sh
-───────────────────────────────────────────────────────────────
-#!/usr/bin/env bash
-
-function set_up() {
-  source validator.sh
-}
-
-function data_provider_valid_emails() {
-  # TODO: Echo valid email addresses, one per line
-  # Example: echo "user@example.com"
-}
-
-function test_valid_emails() {
-  # $1 contains the email from data provider
-  # TODO: Assert is_valid_email succeeds
-  # Hint: assert_successful_code "is_valid_email \"$1\""
-}
-
-function data_provider_invalid_emails() {
-  # TODO: Echo invalid email addresses, one per line
-  # Example: echo "not-an-email"
-}
-
-function test_invalid_emails() {
-  # TODO: Assert is_valid_email fails
-  # Hint: assert_general_error "is_valid_email \"$1\""
-}
-───────────────────────────────────────────────────────────────
-
-TIPS:
-  • Data providers must be named: data_provider_<test_name>
-  • Each line of output becomes one test case
-  • The test function receives the line as $1
-  • Great for testing multiple inputs without duplicating code
-  • You can have multiple data provider/test pairs in one file
-EOF
-
-  local default_file="validator_test.sh"
-  echo ""
-  printf "When ready, enter TEST file path %s[%s]%s: " \
-    "${_BASHUNIT_COLOR_FAINT}" "$default_file" "${_BASHUNIT_COLOR_DEFAULT}"
-  read -r test_file
-  test_file="${test_file:-$default_file}"
-
-  if [ ! -f "$test_file" ]; then
-    local template='#!/usr/bin/env bash
-
-function set_up() {
-  source validator.sh
-}
-
-function data_provider_valid_emails() {
-  # TODO: Echo valid email addresses, one per line
-  # Example: echo "user@example.com"
-}
-
-function test_valid_emails() {
-  # $1 contains the email from data provider
-  # TODO: Assert is_valid_email succeeds
-  # Hint: assert_successful_code "is_valid_email \"$1\""
-}
-
-function data_provider_invalid_emails() {
-  # TODO: Echo invalid email addresses, one per line
-  # Example: echo "not-an-email"
-}
-
-function test_invalid_emails() {
-  # TODO: Assert is_valid_email fails
-  # Hint: assert_general_error "is_valid_email \"$1\""
-}'
-
-    bashunit::learn::create_example_file "$test_file" "$template"
-    return 1
-  fi
-
-  if [ "$("$GREP" -c "function data_provider_" "$test_file" || true)" -eq 0 ]; then
-    echo "${_BASHUNIT_COLOR_FAILED}Your test should define data provider functions${_BASHUNIT_COLOR_DEFAULT}"
-    read -p "Press Enter to continue..." -r
-    return 1
-  fi
-
-  bashunit::learn::run_lesson_test "$test_file" 8
-}
-
-##
-# Lesson 9: Exit Codes
-##
-function bashunit::learn::lesson_exit_codes() {
-  clear
-  cat <<'EOF'
-╔════════════════════════════════════════════════════════════════╗
-║             Lesson 9: Testing Exit Codes                       ║
-╚════════════════════════════════════════════════════════════════╝
-
-CONCEPT: Exit codes indicate success (0) or failure (non-zero).
-bashunit provides assertions to test them:
-  • assert_successful_code - expects exit code 0
-  • assert_general_error - expects exit code 1
-  • assert_exit_code N - expects specific exit code N
-
-TASK: Test different exit codes.
-
-File: checker.sh
-───────────────────────────────────────────────────────────────
-#!/usr/bin/env bash
-
-function check_file() {
-  if [ ! -e "$1" ]; then
-    echo "File not found" >&2
-    return 127
-  fi
-
-  if [ ! -r "$1" ]; then
-    echo "Permission denied" >&2
-    return 1
-  fi
-
-  echo "File OK"
-  return 0
-}
-───────────────────────────────────────────────────────────────
-
-File: checker_test.sh
-───────────────────────────────────────────────────────────────
-#!/usr/bin/env bash
-
-function set_up() {
-  source checker.sh
-  # Create a test file
-  export TEST_FILE="/tmp/test_file_$$"
-  touch "$TEST_FILE"
-}
-
-function tear_down() {
-  rm -f "$TEST_FILE"
-}
-
-function test_existing_file_returns_success() {
-  # TODO: Assert check_file succeeds with TEST_FILE
-  # Hint: assert_successful_code "check_file '$TEST_FILE'"
-}
-
-function test_missing_file_returns_127() {
-  # TODO: Assert check_file returns exit code 127 for missing file
-  # Hint: assert_exit_code 127 "check_file '/nonexistent/file'"
-}
-───────────────────────────────────────────────────────────────
-
-TIPS:
-  • Exit code 0 = success (assert_successful_code)
-  • Exit code 1 = general error (assert_general_error)
-  • Other codes = specific errors (assert_exit_code N)
-  • Bash uses 'return N' in functions, 'exit N' in scripts
-  • Common codes: 127=not found, 126=not executable, 2=misuse
-EOF
-
-  local default_file="checker_test.sh"
-  echo ""
-  printf "When ready, enter TEST file path %s[%s]%s: " \
-    "${_BASHUNIT_COLOR_FAINT}" "$default_file" "${_BASHUNIT_COLOR_DEFAULT}"
-  read -r test_file
-  test_file="${test_file:-$default_file}"
-
-  if [ ! -f "$test_file" ]; then
-    local template='#!/usr/bin/env bash
-
-function set_up() {
-  source checker.sh
-  # Create a test file
-  export TEST_FILE="/tmp/test_file_$$"
-  touch "$TEST_FILE"
-}
-
-function tear_down() {
-  rm -f "$TEST_FILE"
-}
-
-function test_existing_file_returns_success() {
-  # TODO: Assert check_file succeeds with TEST_FILE
-  # Hint: assert_successful_code "check_file '\''$TEST_FILE'\''"
-}
-
-function test_missing_file_returns_127() {
-  # TODO: Assert check_file returns exit code 127 for missing file
-  # Hint: assert_exit_code 127 "check_file '\''/nonexistent/file'\''"
-}'
-
-    bashunit::learn::create_example_file "$test_file" "$template"
-    return 1
-  fi
-
-  local _exit_assert_pattern="assert_successful_code\|assert_exit_code\|assert_general_error"
-  if [ "$("$GREP" -c "$_exit_assert_pattern" "$test_file" || true)" -eq 0 ]; then
-    echo "${_BASHUNIT_COLOR_FAILED}Your test should use exit code assertions${_BASHUNIT_COLOR_DEFAULT}"
-    read -p "Press Enter to continue..." -r
-    return 1
-  fi
-
-  bashunit::learn::run_lesson_test "$test_file" 9
-}
-
-##
-# Lesson 10: Complete Challenge
-##
-function bashunit::learn::lesson_challenge() {
-  clear
-  cat <<'EOF'
-╔════════════════════════════════════════════════════════════════╗
-║          Lesson 10: Complete Challenge - Backup Script         ║
-╚════════════════════════════════════════════════════════════════╝
-
-FINAL CHALLENGE: Combine everything you've learned!
-
-CONCEPT: Real-world tests combine multiple concepts: lifecycle
-management, assertions, exit codes, and test doubles.
-
-TASK: Create a backup script and comprehensive tests.
-
-File: backup.sh
-───────────────────────────────────────────────────────────────
-#!/usr/bin/env bash
-
-function create_backup() {
-  local source=$1
-  local dest=$2
-
-  if [ ! -d "$source" ]; then
-    echo "Source directory not found" >&2
-    return 1
-  fi
-
-  tar -czf "$dest" -C "$source" .
-  echo "Backup created: $dest"
-}
-───────────────────────────────────────────────────────────────
-
-File: backup_test.sh
-───────────────────────────────────────────────────────────────
-#!/usr/bin/env bash
-
-Your test must include:
-  1. set_up and tear_down functions
-  2. Test successful backup creation
-  3. Test failure when source doesn't exist
-  4. Mock or spy on tar command
-  5. Verify backup file exists
-  6. Check output message
-
-TIP: Combine patterns from all previous lessons!
-EOF
-
-  local default_file="backup_test.sh"
-  echo ""
-  printf "When ready, enter TEST file path %s[%s]%s: " \
-    "${_BASHUNIT_COLOR_FAINT}" "$default_file" "${_BASHUNIT_COLOR_DEFAULT}"
-  read -r test_file
-  test_file="${test_file:-$default_file}"
-
-  if [ ! -f "$test_file" ]; then
-    local template='#!/usr/bin/env bash
-
-function set_up() {
-  source backup.sh
-  # TODO: Create test directories and variables
-}
-
-function tear_down() {
-  # TODO: Clean up test files
-}
-
-function test_successful_backup() {
-  # TODO: Test backup creation
-}
-
-function test_backup_failure_when_source_missing() {
-  # TODO: Test failure case
-}
-
-# Add more tests as needed:
-# - Mock or spy on tar command
-# - Verify backup file exists
-# - Check output message
-#
-# TIPS:
-# - Combine lifecycle (set_up/tear_down) with file assertions
-# - Use spies to verify tar was called correctly
-# - Test both success and failure scenarios
-# - Mock external commands to avoid side effects'
-
-    bashunit::learn::create_example_file "$test_file" "$template"
-    return 1
-  fi
-
-  # Verify the test has key components
-  local -a missing_components=()
-  local missing_components_count=0
-
-  if [ "$("$GREP" -c "function set_up()" "$test_file" || true)" -eq 0 ]; then
-    missing_components[missing_components_count]="set_up function"
-    missing_components_count=$((missing_components_count + 1))
-  fi
-
-  if [ "$("$GREP" -c "function tear_down()" "$test_file" || true)" -eq 0 ]; then
-    missing_components[missing_components_count]="tear_down function"
-    missing_components_count=$((missing_components_count + 1))
-  fi
-
-  if [ "$missing_components_count" -gt 0 ]; then
-    echo "${_BASHUNIT_COLOR_FAILED}Missing required components:${_BASHUNIT_COLOR_DEFAULT}"
-    printf "  - %s\n" "${missing_components[@]}"
-    read -p "Press Enter to continue..." -r
-    return 1
-  fi
-
-  if bashunit::learn::run_lesson_test "$test_file" 10; then
-    echo ""
-    echo "${_BASHUNIT_COLOR_PASSED}${_BASHUNIT_COLOR_BOLD}"
-    cat <<'EOF'
-╔════════════════════════════════════════════════════════════════╗
-║                   🎉 CONGRATULATIONS! 🎉                       ║
-║                                                                ║
-║          You've completed all bashunit lessons!                ║
-║                                                                ║
-║  You now know how to:                                          ║
-║    ✓ Write and run tests                                       ║
-║    ✓ Use various assertions                                    ║
-║    ✓ Manage test lifecycle                                     ║
-║    ✓ Test functions and scripts                                ║
-║    ✓ Mock external dependencies                                ║
-║    ✓ Spy on function calls                                     ║
-║    ✓ Use data providers                                        ║
-║    ✓ Test exit codes                                           ║
-║                                                                ║
-║  Next steps:                                                   ║
-║    • Explore https://bashunit.com                              ║
-║    • Check out /common-patterns for more examples              ║
-║    • Start testing your own bash scripts!                      ║
-╚════════════════════════════════════════════════════════════════╝
-EOF
-    echo "${_BASHUNIT_COLOR_DEFAULT}"
-    read -p "Press Enter to continue..." -r
-  fi
-}
diff --git a/src/learn/index.sh b/src/learn/index.sh
new file mode 100644
index 00000000..4e3e7aff
--- /dev/null
+++ b/src/learn/index.sh
@@ -0,0 +1,26 @@
+#!/usr/bin/env bash
+
+# Interactive learning module for bashunit: guided tutorials and exercises.
+#
+# Entry point for the src/learn/ module: only `source` lines and comments belong
+# here. build.sh emits a file's body before recursing into its `source` lines, so
+# any statement here would run before its dependencies in the built binary
+# (adrs/adr-010-src-module-directories.md).
+#
+# Sourced in dependency layers, leaves first:
+#   progress -> session -> lessons -> menu
+# Every lesson calls only session's create_example_file and run_lesson_test; no
+# lesson calls another, so the ten are mutually independent.
+source "$BASHUNIT_ROOT_DIR/src/learn/progress.sh"
+source "$BASHUNIT_ROOT_DIR/src/learn/session.sh"
+source "$BASHUNIT_ROOT_DIR/src/learn/lessons/basics.sh"
+source "$BASHUNIT_ROOT_DIR/src/learn/lessons/assertions.sh"
+source "$BASHUNIT_ROOT_DIR/src/learn/lessons/lifecycle.sh"
+source "$BASHUNIT_ROOT_DIR/src/learn/lessons/functions.sh"
+source "$BASHUNIT_ROOT_DIR/src/learn/lessons/scripts.sh"
+source "$BASHUNIT_ROOT_DIR/src/learn/lessons/mocking.sh"
+source "$BASHUNIT_ROOT_DIR/src/learn/lessons/spies.sh"
+source "$BASHUNIT_ROOT_DIR/src/learn/lessons/data_providers.sh"
+source "$BASHUNIT_ROOT_DIR/src/learn/lessons/exit_codes.sh"
+source "$BASHUNIT_ROOT_DIR/src/learn/lessons/challenge.sh"
+source "$BASHUNIT_ROOT_DIR/src/learn/menu.sh"
diff --git a/src/learn/lessons/assertions.sh b/src/learn/lessons/assertions.sh
new file mode 100644
index 00000000..e80345c5
--- /dev/null
+++ b/src/learn/lessons/assertions.sh
@@ -0,0 +1,88 @@
+#!/usr/bin/env bash
+# shellcheck disable=SC2016  # lesson text shows literal $vars in single quotes
+
+# The "assertions" lesson.
+
+##
+# Lesson 2: Assertions - Testing Different Conditions
+##
+function bashunit::learn::lesson_assertions() {
+  clear
+  cat <<'EOF'
+╔════════════════════════════════════════════════════════════════╗
+║              Lesson 2: Testing Different Conditions            ║
+╚════════════════════════════════════════════════════════════════╝
+
+CONCEPT: bashunit provides many assertion functions for different checks:
+  • assert_same - exact equality
+  • assert_contains - substring check
+  • assert_matches - regex pattern
+  • assert_not_same - inequality
+  • assert_empty - checks if value is empty
+  • assert_not_empty - checks if value is not empty
+
+TASK: Write a test file with 3 different assertions.
+
+File: tests/assertions_test.sh
+───────────────────────────────────────────────────────────────
+#!/usr/bin/env bash
+
+function test_multiple_assertions() {
+  local message="Hello, bashunit!"
+
+  # TODO: Check that message contains "bashunit"
+  # Hint: assert_contains "substring" "$message"
+
+  # TODO: Check that message matches the pattern "Hello.*!"
+  # Hint: assert_matches "pattern" "$message"
+
+  # TODO: Check that message is not empty
+  # Hint: assert_not_empty "$message"
+}
+───────────────────────────────────────────────────────────────
+
+TIPS:
+  • assert_same checks exact equality (useful for strings/numbers)
+  • assert_contains is more flexible for partial matches
+  • assert_matches uses regex patterns (e.g., "^[0-9]+$" for numbers)
+  • Explore more: assert_empty, assert_true, assert_false
+EOF
+
+  local default_file="tests/assertions_test.sh"
+  echo ""
+  printf "When ready, enter file path %s[%s]%s: " \
+    "${_BASHUNIT_COLOR_FAINT}" "$default_file" "${_BASHUNIT_COLOR_DEFAULT}"
+  read -r test_file
+  test_file="${test_file:-$default_file}"
+
+  if [ ! -f "$test_file" ]; then
+    local template='#!/usr/bin/env bash
+
+function test_multiple_assertions() {
+  local message="Hello, bashunit!"
+
+  # TODO: Check that message contains "bashunit"
+  # Hint: assert_contains "substring" "$message"
+
+  # TODO: Check that message matches the pattern "Hello.*!"
+  # Hint: assert_matches "pattern" "$message"
+
+  # TODO: Check that message is not empty
+  # Hint: assert_not_empty "$message"
+}'
+
+    bashunit::learn::create_example_file "$test_file" "$template"
+    return 1
+  fi
+
+  if [ "$("$GREP" -c "assert_contains" "$test_file" || true)" -eq 0 ] ||
+    [ "$("$GREP" -c "assert_matches" "$test_file" || true)" -eq 0 ] ||
+    [ "$("$GREP" -c "assert_not_empty" "$test_file" || true)" -eq 0 ]; then
+    echo "${_BASHUNIT_COLOR_FAILED}Your test should use all three assertion types${_BASHUNIT_COLOR_DEFAULT}"
+    read -p "Press Enter to continue..." -r
+    return 1
+  fi
+
+  bashunit::learn::run_lesson_test "$test_file" 2
+}
+
diff --git a/src/learn/lessons/basics.sh b/src/learn/lessons/basics.sh
new file mode 100644
index 00000000..b182d202
--- /dev/null
+++ b/src/learn/lessons/basics.sh
@@ -0,0 +1,68 @@
+#!/usr/bin/env bash
+
+# The "basics" lesson.
+
+##
+# Lesson 1: Basics - Your First Test
+##
+function bashunit::learn::lesson_basics() {
+  clear
+  cat <<'EOF'
+╔════════════════════════════════════════════════════════════════╗
+║                    Lesson 1: Your First Test                   ║
+╚════════════════════════════════════════════════════════════════╝
+
+Welcome to bashunit! Let's write your first test.
+
+CONCEPT: A test is a function that starts with 'test_' and uses
+assertions to verify behavior.
+
+TASK: Create a test file that checks if two values are equal.
+
+File: tests/first_test.sh
+───────────────────────────────────────────────────────────────
+#!/usr/bin/env bash
+
+function test_bashunit_works() {
+  # TODO: Use assert_same to check if "hello" equals "hello"
+  # Hint: assert_same "expected" "actual"
+}
+───────────────────────────────────────────────────────────────
+
+TIPS:
+  • The assert_same function takes two arguments:
+    assert_same "expected" "actual"
+  • Test functions must start with "test_" prefix
+  • Always quote your strings to avoid word splitting
+  • Keep test files in a tests/ directory for better organization
+EOF
+
+  local default_file="tests/first_test.sh"
+  echo ""
+  printf "When ready, enter file path %s[%s]%s: " \
+    "${_BASHUNIT_COLOR_FAINT}" "$default_file" "${_BASHUNIT_COLOR_DEFAULT}"
+  read -r test_file
+  test_file="${test_file:-$default_file}"
+
+  if [ ! -f "$test_file" ]; then
+    local template='#!/usr/bin/env bash
+
+function test_bashunit_works() {
+  # TODO: Use assert_same to check if "hello" equals "hello"
+  # Hint: assert_same "expected" "actual"
+}'
+
+    bashunit::learn::create_example_file "$test_file" "$template"
+    return 1
+  fi
+
+  # Check if file contains assert_same
+  if [ "$("$GREP" -c "assert_same" "$test_file" || true)" -eq 0 ]; then
+    echo "${_BASHUNIT_COLOR_FAILED}Your test should use assert_same${_BASHUNIT_COLOR_DEFAULT}"
+    read -p "Press Enter to continue..." -r
+    return 1
+  fi
+
+  bashunit::learn::run_lesson_test "$test_file" 1
+}
+
diff --git a/src/learn/lessons/challenge.sh b/src/learn/lessons/challenge.sh
new file mode 100644
index 00000000..0c7411b2
--- /dev/null
+++ b/src/learn/lessons/challenge.sh
@@ -0,0 +1,146 @@
+#!/usr/bin/env bash
+
+# The "challenge" lesson.
+
+##
+# Lesson 10: Complete Challenge
+##
+function bashunit::learn::lesson_challenge() {
+  clear
+  cat <<'EOF'
+╔════════════════════════════════════════════════════════════════╗
+║          Lesson 10: Complete Challenge - Backup Script         ║
+╚════════════════════════════════════════════════════════════════╝
+
+FINAL CHALLENGE: Combine everything you've learned!
+
+CONCEPT: Real-world tests combine multiple concepts: lifecycle
+management, assertions, exit codes, and test doubles.
+
+TASK: Create a backup script and comprehensive tests.
+
+File: backup.sh
+───────────────────────────────────────────────────────────────
+#!/usr/bin/env bash
+
+function create_backup() {
+  local source=$1
+  local dest=$2
+
+  if [ ! -d "$source" ]; then
+    echo "Source directory not found" >&2
+    return 1
+  fi
+
+  tar -czf "$dest" -C "$source" .
+  echo "Backup created: $dest"
+}
+───────────────────────────────────────────────────────────────
+
+File: backup_test.sh
+───────────────────────────────────────────────────────────────
+#!/usr/bin/env bash
+
+Your test must include:
+  1. set_up and tear_down functions
+  2. Test successful backup creation
+  3. Test failure when source doesn't exist
+  4. Mock or spy on tar command
+  5. Verify backup file exists
+  6. Check output message
+
+TIP: Combine patterns from all previous lessons!
+EOF
+
+  local default_file="backup_test.sh"
+  echo ""
+  printf "When ready, enter TEST file path %s[%s]%s: " \
+    "${_BASHUNIT_COLOR_FAINT}" "$default_file" "${_BASHUNIT_COLOR_DEFAULT}"
+  read -r test_file
+  test_file="${test_file:-$default_file}"
+
+  if [ ! -f "$test_file" ]; then
+    local template='#!/usr/bin/env bash
+
+function set_up() {
+  source backup.sh
+  # TODO: Create test directories and variables
+}
+
+function tear_down() {
+  # TODO: Clean up test files
+}
+
+function test_successful_backup() {
+  # TODO: Test backup creation
+}
+
+function test_backup_failure_when_source_missing() {
+  # TODO: Test failure case
+}
+
+# Add more tests as needed:
+# - Mock or spy on tar command
+# - Verify backup file exists
+# - Check output message
+#
+# TIPS:
+# - Combine lifecycle (set_up/tear_down) with file assertions
+# - Use spies to verify tar was called correctly
+# - Test both success and failure scenarios
+# - Mock external commands to avoid side effects'
+
+    bashunit::learn::create_example_file "$test_file" "$template"
+    return 1
+  fi
+
+  # Verify the test has key components
+  local -a missing_components=()
+  local missing_components_count=0
+
+  if [ "$("$GREP" -c "function set_up()" "$test_file" || true)" -eq 0 ]; then
+    missing_components[missing_components_count]="set_up function"
+    missing_components_count=$((missing_components_count + 1))
+  fi
+
+  if [ "$("$GREP" -c "function tear_down()" "$test_file" || true)" -eq 0 ]; then
+    missing_components[missing_components_count]="tear_down function"
+    missing_components_count=$((missing_components_count + 1))
+  fi
+
+  if [ "$missing_components_count" -gt 0 ]; then
+    echo "${_BASHUNIT_COLOR_FAILED}Missing required components:${_BASHUNIT_COLOR_DEFAULT}"
+    printf "  - %s\n" "${missing_components[@]}"
+    read -p "Press Enter to continue..." -r
+    return 1
+  fi
+
+  if bashunit::learn::run_lesson_test "$test_file" 10; then
+    echo ""
+    echo "${_BASHUNIT_COLOR_PASSED}${_BASHUNIT_COLOR_BOLD}"
+    cat <<'EOF'
+╔════════════════════════════════════════════════════════════════╗
+║                   🎉 CONGRATULATIONS! 🎉                       ║
+║                                                                ║
+║          You've completed all bashunit lessons!                ║
+║                                                                ║
+║  You now know how to:                                          ║
+║    ✓ Write and run tests                                       ║
+║    ✓ Use various assertions                                    ║
+║    ✓ Manage test lifecycle                                     ║
+║    ✓ Test functions and scripts                                ║
+║    ✓ Mock external dependencies                                ║
+║    ✓ Spy on function calls                                     ║
+║    ✓ Use data providers                                        ║
+║    ✓ Test exit codes                                           ║
+║                                                                ║
+║  Next steps:                                                   ║
+║    • Explore https://bashunit.com                              ║
+║    • Check out /common-patterns for more examples              ║
+║    • Start testing your own bash scripts!                      ║
+╚════════════════════════════════════════════════════════════════╝
+EOF
+    echo "${_BASHUNIT_COLOR_DEFAULT}"
+    read -p "Press Enter to continue..." -r
+  fi
+}
diff --git a/src/learn/lessons/data_providers.sh b/src/learn/lessons/data_providers.sh
new file mode 100644
index 00000000..51cc6c3d
--- /dev/null
+++ b/src/learn/lessons/data_providers.sh
@@ -0,0 +1,119 @@
+#!/usr/bin/env bash
+# shellcheck disable=SC2016  # lesson text shows literal $vars in single quotes
+
+# The "data_providers" lesson.
+
+##
+# Lesson 8: Data Providers
+##
+function bashunit::learn::lesson_data_providers() {
+  clear
+  cat <<'EOF'
+╔════════════════════════════════════════════════════════════════╗
+║           Lesson 8: Data Providers - Parameterized Tests       ║
+╚════════════════════════════════════════════════════════════════╝
+
+CONCEPT: Data providers let you run the same test with different inputs.
+Define a function that echoes test data, one per line.
+
+HOW IT WORKS: Each line from data_provider_* becomes $1 in your test.
+The test runs once for each line of data.
+
+TASK: Test multiple email formats using a data provider.
+
+File: validator.sh
+───────────────────────────────────────────────────────────────
+#!/usr/bin/env bash
+
+function is_valid_email() {
+  local email_pattern='^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$'
+  [ "$(echo "$1" | "$GREP" -cE "$email_pattern" || true)" -gt 0 ]
+}
+───────────────────────────────────────────────────────────────
+
+File: validator_test.sh
+───────────────────────────────────────────────────────────────
+#!/usr/bin/env bash
+
+function set_up() {
+  source validator.sh
+}
+
+function data_provider_valid_emails() {
+  # TODO: Echo valid email addresses, one per line
+  # Example: echo "user@example.com"
+}
+
+function test_valid_emails() {
+  # $1 contains the email from data provider
+  # TODO: Assert is_valid_email succeeds
+  # Hint: assert_successful_code "is_valid_email \"$1\""
+}
+
+function data_provider_invalid_emails() {
+  # TODO: Echo invalid email addresses, one per line
+  # Example: echo "not-an-email"
+}
+
+function test_invalid_emails() {
+  # TODO: Assert is_valid_email fails
+  # Hint: assert_general_error "is_valid_email \"$1\""
+}
+───────────────────────────────────────────────────────────────
+
+TIPS:
+  • Data providers must be named: data_provider_<test_name>
+  • Each line of output becomes one test case
+  • The test function receives the line as $1
+  • Great for testing multiple inputs without duplicating code
+  • You can have multiple data provider/test pairs in one file
+EOF
+
+  local default_file="validator_test.sh"
+  echo ""
+  printf "When ready, enter TEST file path %s[%s]%s: " \
+    "${_BASHUNIT_COLOR_FAINT}" "$default_file" "${_BASHUNIT_COLOR_DEFAULT}"
+  read -r test_file
+  test_file="${test_file:-$default_file}"
+
+  if [ ! -f "$test_file" ]; then
+    local template='#!/usr/bin/env bash
+
+function set_up() {
+  source validator.sh
+}
+
+function data_provider_valid_emails() {
+  # TODO: Echo valid email addresses, one per line
+  # Example: echo "user@example.com"
+}
+
+function test_valid_emails() {
+  # $1 contains the email from data provider
+  # TODO: Assert is_valid_email succeeds
+  # Hint: assert_successful_code "is_valid_email \"$1\""
+}
+
+function data_provider_invalid_emails() {
+  # TODO: Echo invalid email addresses, one per line
+  # Example: echo "not-an-email"
+}
+
+function test_invalid_emails() {
+  # TODO: Assert is_valid_email fails
+  # Hint: assert_general_error "is_valid_email \"$1\""
+}'
+
+    bashunit::learn::create_example_file "$test_file" "$template"
+    return 1
+  fi
+
+  if [ "$("$GREP" -c "function data_provider_" "$test_file" || true)" -eq 0 ]; then
+    echo "${_BASHUNIT_COLOR_FAILED}Your test should define data provider functions${_BASHUNIT_COLOR_DEFAULT}"
+    read -p "Press Enter to continue..." -r
+    return 1
+  fi
+
+  bashunit::learn::run_lesson_test "$test_file" 8
+}
+
diff --git a/src/learn/lessons/exit_codes.sh b/src/learn/lessons/exit_codes.sh
new file mode 100644
index 00000000..dbebb1c3
--- /dev/null
+++ b/src/learn/lessons/exit_codes.sh
@@ -0,0 +1,122 @@
+#!/usr/bin/env bash
+# shellcheck disable=SC2016  # lesson text shows literal $vars in single quotes
+
+# The "exit_codes" lesson.
+
+##
+# Lesson 9: Exit Codes
+##
+function bashunit::learn::lesson_exit_codes() {
+  clear
+  cat <<'EOF'
+╔════════════════════════════════════════════════════════════════╗
+║             Lesson 9: Testing Exit Codes                       ║
+╚════════════════════════════════════════════════════════════════╝
+
+CONCEPT: Exit codes indicate success (0) or failure (non-zero).
+bashunit provides assertions to test them:
+  • assert_successful_code - expects exit code 0
+  • assert_general_error - expects exit code 1
+  • assert_exit_code N - expects specific exit code N
+
+TASK: Test different exit codes.
+
+File: checker.sh
+───────────────────────────────────────────────────────────────
+#!/usr/bin/env bash
+
+function check_file() {
+  if [ ! -e "$1" ]; then
+    echo "File not found" >&2
+    return 127
+  fi
+
+  if [ ! -r "$1" ]; then
+    echo "Permission denied" >&2
+    return 1
+  fi
+
+  echo "File OK"
+  return 0
+}
+───────────────────────────────────────────────────────────────
+
+File: checker_test.sh
+───────────────────────────────────────────────────────────────
+#!/usr/bin/env bash
+
+function set_up() {
+  source checker.sh
+  # Create a test file
+  export TEST_FILE="/tmp/test_file_$$"
+  touch "$TEST_FILE"
+}
+
+function tear_down() {
+  rm -f "$TEST_FILE"
+}
+
+function test_existing_file_returns_success() {
+  # TODO: Assert check_file succeeds with TEST_FILE
+  # Hint: assert_successful_code "check_file '$TEST_FILE'"
+}
+
+function test_missing_file_returns_127() {
+  # TODO: Assert check_file returns exit code 127 for missing file
+  # Hint: assert_exit_code 127 "check_file '/nonexistent/file'"
+}
+───────────────────────────────────────────────────────────────
+
+TIPS:
+  • Exit code 0 = success (assert_successful_code)
+  • Exit code 1 = general error (assert_general_error)
+  • Other codes = specific errors (assert_exit_code N)
+  • Bash uses 'return N' in functions, 'exit N' in scripts
+  • Common codes: 127=not found, 126=not executable, 2=misuse
+EOF
+
+  local default_file="checker_test.sh"
+  echo ""
+  printf "When ready, enter TEST file path %s[%s]%s: " \
+    "${_BASHUNIT_COLOR_FAINT}" "$default_file" "${_BASHUNIT_COLOR_DEFAULT}"
+  read -r test_file
+  test_file="${test_file:-$default_file}"
+
+  if [ ! -f "$test_file" ]; then
+    local template='#!/usr/bin/env bash
+
+function set_up() {
+  source checker.sh
+  # Create a test file
+  export TEST_FILE="/tmp/test_file_$$"
+  touch "$TEST_FILE"
+}
+
+function tear_down() {
+  rm -f "$TEST_FILE"
+}
+
+function test_existing_file_returns_success() {
+  # TODO: Assert check_file succeeds with TEST_FILE
+  # Hint: assert_successful_code "check_file '\''$TEST_FILE'\''"
+}
+
+function test_missing_file_returns_127() {
+  # TODO: Assert check_file returns exit code 127 for missing file
+  # Hint: assert_exit_code 127 "check_file '\''/nonexistent/file'\''"
+}'
+
+    bashunit::learn::create_example_file "$test_file" "$template"
+    return 1
+  fi
+
+  local _exit_assert_pattern="assert_successful_code\|assert_exit_code\|assert_general_error"
+  if [ "$("$GREP" -c "$_exit_assert_pattern" "$test_file" || true)" -eq 0 ]; then
+    echo "${_BASHUNIT_COLOR_FAILED}Your test should use exit code assertions${_BASHUNIT_COLOR_DEFAULT}"
+    read -p "Press Enter to continue..." -r
+    return 1
+  fi
+
+  bashunit::learn::run_lesson_test "$test_file" 9
+}
+
diff --git a/src/learn/lessons/functions.sh b/src/learn/lessons/functions.sh
new file mode 100644
index 00000000..d3acdd6f
--- /dev/null
+++ b/src/learn/lessons/functions.sh
@@ -0,0 +1,98 @@
+#!/usr/bin/env bash
+# shellcheck disable=SC2016  # lesson text shows literal $vars in single quotes
+
+# The "functions" lesson.
+
+##
+# Lesson 4: Testing Functions
+##
+function bashunit::learn::lesson_functions() {
+  clear
+  cat <<'EOF'
+╔════════════════════════════════════════════════════════════════╗
+║              Lesson 4: Testing Bash Functions                  ║
+╚════════════════════════════════════════════════════════════════╝
+
+CONCEPT: To test functions, source the file containing them, then
+call them in your tests.
+
+TASK: Create a script with a function, then test it.
+
+File: calculator.sh (source code)
+───────────────────────────────────────────────────────────────
+#!/usr/bin/env bash
+
+function add() {
+  echo $(($1 + $2))
+}
+───────────────────────────────────────────────────────────────
+
+File: tests/calculator_test.sh (test file)
+───────────────────────────────────────────────────────────────
+#!/usr/bin/env bash
+
+function set_up() {
+  # TODO: Source calculator.sh from parent directory
+  # Hint: source ../calculator.sh
+}
+
+function test_add_positive_numbers() {
+  # TODO: Test that add 2 3 returns "5"
+  # Hint: result=$(add 2 3)
+  # Hint: assert_same "5" "$result"
+}
+
+function test_add_negative_numbers() {
+  # TODO: Test that add -2 -3 returns "-5"
+  # Hint: result=$(add -2 -3)
+  # Hint: assert_same "-5" "$result"
+}
+───────────────────────────────────────────────────────────────
+
+TIPS:
+  • Source files in set_up() to reload them fresh for each test
+  • Capture function output with: result=$(function_name args)
+  • Test edge cases: positive, negative, zero, large numbers
+  • Source files from parent directory: source ../file.sh
+EOF
+
+  local default_file="tests/calculator_test.sh"
+  echo ""
+  printf "When ready, enter TEST file path %s[%s]%s: " \
+    "${_BASHUNIT_COLOR_FAINT}" "$default_file" "${_BASHUNIT_COLOR_DEFAULT}"
+  read -r test_file
+  test_file="${test_file:-$default_file}"
+
+  if [ ! -f "$test_file" ]; then
+    local template='#!/usr/bin/env bash
+
+function set_up() {
+  # TODO: Source calculator.sh from parent directory
+  # Hint: source ../calculator.sh
+}
+
+function test_add_positive_numbers() {
+  # TODO: Test that add 2 3 returns "5"
+  # Hint: result=$(add 2 3)
+  # Hint: assert_same "5" "$result"
+}
+
+function test_add_negative_numbers() {
+  # TODO: Test that add -2 -3 returns "-5"
+  # Hint: result=$(add -2 -3)
+  # Hint: assert_same "-5" "$result"
+}'
+
+    bashunit::learn::create_example_file "$test_file" "$template"
+    return 1
+  fi
+
+  if [ "$("$GREP" -c "source" "$test_file" || true)" -eq 0 ]; then
+    echo "${_BASHUNIT_COLOR_FAILED}Your test should source the calculator.sh file${_BASHUNIT_COLOR_DEFAULT}"
+    read -p "Press Enter to continue..." -r
+    return 1
+  fi
+
+  bashunit::learn::run_lesson_test "$test_file" 4
+}
+
diff --git a/src/learn/lessons/lifecycle.sh b/src/learn/lessons/lifecycle.sh
new file mode 100644
index 00000000..e22ae72c
--- /dev/null
+++ b/src/learn/lessons/lifecycle.sh
@@ -0,0 +1,97 @@
+#!/usr/bin/env bash
+# shellcheck disable=SC2016  # lesson text shows literal $vars in single quotes
+
+# The "lifecycle" lesson.
+
+##
+# Lesson 3: Setup & Teardown - Managing Test Lifecycle
+##
+function bashunit::learn::lesson_lifecycle() {
+  clear
+  cat <<'EOF'
+╔════════════════════════════════════════════════════════════════╗
+║           Lesson 3: Setup and Teardown Functions               ║
+╚════════════════════════════════════════════════════════════════╝
+
+CONCEPT: Tests often need preparation and cleanup. bashunit provides:
+  • set_up() - runs before EACH test
+  • tear_down() - runs after EACH test
+  • set_up_before_script() - runs once before ALL tests
+  • tear_down_after_script() - runs once after ALL tests
+
+TASK: Create a test that uses setup and teardown to manage files.
+
+File: tests/lifecycle_test.sh
+───────────────────────────────────────────────────────────────
+#!/usr/bin/env bash
+
+function set_up() {
+  # Create a temp file before each test
+  # TODO: export TEST_FILE="/tmp/test_$$"
+  # TODO: echo "test content" > "$TEST_FILE"
+}
+
+function tear_down() {
+  # Clean up after each test
+  # TODO: rm -f "$TEST_FILE"
+}
+
+function test_file_exists() {
+  # TODO: assert_file_exists "$TEST_FILE"
+}
+
+function test_file_has_content() {
+  # TODO: assert_file_contains "test content" "$TEST_FILE"
+}
+───────────────────────────────────────────────────────────────
+
+TIPS:
+  • set_up() runs before EACH test (good for test isolation)
+  • set_up_before_script() runs ONCE before all tests (good for expensive setup)
+  • Always clean up in tear_down() to avoid polluting other tests
+  • Use $$ for unique temp file names to avoid conflicts
+EOF
+
+  local default_file="tests/lifecycle_test.sh"
+  echo ""
+  printf "When ready, enter file path %s[%s]%s: " \
+    "${_BASHUNIT_COLOR_FAINT}" "$default_file" "${_BASHUNIT_COLOR_DEFAULT}"
+  read -r test_file
+  test_file="${test_file:-$default_file}"
+
+  if [ ! -f "$test_file" ]; then
+    local template='#!/usr/bin/env bash
+
+function set_up() {
+  # Create a temp file before each test
+  # TODO: export TEST_FILE="/tmp/test_$$"
+  # TODO: echo "test content" > "$TEST_FILE"
+}
+
+function tear_down() {
+  # Clean up after each test
+  # TODO: rm -f "$TEST_FILE"
+}
+
+function test_file_exists() {
+  # TODO: assert_file_exists "$TEST_FILE"
+}
+
+function test_file_has_content() {
+  # TODO: assert_file_contains "test content" "$TEST_FILE"
+}'
+
+    bashunit::learn::create_example_file "$test_file" "$template"
+    return 1
+  fi
+
+  if [ "$("$GREP" -c "function set_up()" "$test_file" || true)" -eq 0 ] ||
+    [ "$("$GREP" -c "function tear_down()" "$test_file" || true)" -eq 0 ]; then
+    echo "${_BASHUNIT_COLOR_FAILED}Your test should define set_up and tear_down functions${_BASHUNIT_COLOR_DEFAULT}"
+    read -p "Press Enter to continue..." -r
+    return 1
+  fi
+
+  bashunit::learn::run_lesson_test "$test_file" 3
+}
+
diff --git a/src/learn/lessons/mocking.sh b/src/learn/lessons/mocking.sh
new file mode 100644
index 00000000..e6c61797
--- /dev/null
+++ b/src/learn/lessons/mocking.sh
@@ -0,0 +1,110 @@
+#!/usr/bin/env bash
+# shellcheck disable=SC2016  # lesson text shows literal $vars in single quotes
+
+# The "mocking" lesson.
+
+##
+# Lesson 6: Mocking
+##
+function bashunit::learn::lesson_mocking() {
+  clear
+  cat <<'EOF'
+╔════════════════════════════════════════════════════════════════╗
+║               Lesson 6: Mocking External Commands              ║
+╚════════════════════════════════════════════════════════════════╝
+
+CONCEPT: Mocks let you override external commands or functions to
+control their behavior in tests.
+
+TASK: Test a function that uses external commands.
+
+File: system_info.sh (source code)
+───────────────────────────────────────────────────────────────
+#!/usr/bin/env bash
+
+function get_system_info() {
+  echo "OS: $(uname -s)"
+}
+───────────────────────────────────────────────────────────────
+
+File: tests/system_info_test.sh (test file)
+───────────────────────────────────────────────────────────────
+#!/usr/bin/env bash
+
+function set_up() {
+  source ../system_info.sh
+}
+
+function test_system_info_on_linux() {
+  # TODO: Mock uname to return "Linux"
+  # Hint: mock uname echo "Linux"
+
+  local output
+  output=$(get_system_info)
+
+  # TODO: Assert output contains "OS: Linux"
+}
+
+function test_system_info_on_macos() {
+  # TODO: Mock uname to return "Darwin"
+
+  local output
+  output=$(get_system_info)
+
+  # TODO: Assert output contains "OS: Darwin"
+}
+───────────────────────────────────────────────────────────────
+
+TIPS:
+  • Mocks replace commands/functions with custom behavior
+  • Syntax: mock command_name echo "mocked output"
+  • Mocks are automatically cleaned up after each test
+  • Use mocks to avoid calling expensive external commands
+EOF
+
+  local default_file="tests/system_info_test.sh"
+  echo ""
+  printf "When ready, enter TEST file path %s[%s]%s: " \
+    "${_BASHUNIT_COLOR_FAINT}" "$default_file" "${_BASHUNIT_COLOR_DEFAULT}"
+  read -r test_file
+  test_file="${test_file:-$default_file}"
+
+  if [ ! -f "$test_file" ]; then
+    local template='#!/usr/bin/env bash
+
+function set_up() {
+  source ../system_info.sh
+}
+
+function test_system_info_on_linux() {
+  # TODO: Mock uname to return "Linux"
+  # Hint: mock uname echo "Linux"
+
+  local output
+  output=$(get_system_info)
+
+  # TODO: Assert output contains "OS: Linux"
+}
+
+function test_system_info_on_macos() {
+  # TODO: Mock uname to return "Darwin"
+
+  local output
+  output=$(get_system_info)
+
+  # TODO: Assert output contains "OS: Darwin"
+}'
+
+    bashunit::learn::create_example_file "$test_file" "$template"
+    return 1
+  fi
+
+  if [ "$("$GREP" -c "mock" "$test_file" || true)" -eq 0 ]; then
+    echo "${_BASHUNIT_COLOR_FAILED}Your test should use mock${_BASHUNIT_COLOR_DEFAULT}"
+    read -p "Press Enter to continue..." -r
+    return 1
+  fi
+
+  bashunit::learn::run_lesson_test "$test_file" 6
+}
+
diff --git a/src/learn/lessons/scripts.sh b/src/learn/lessons/scripts.sh
new file mode 100644
index 00000000..3afcdd73
--- /dev/null
+++ b/src/learn/lessons/scripts.sh
@@ -0,0 +1,89 @@
+#!/usr/bin/env bash
+# shellcheck disable=SC2016  # lesson text shows literal $vars in single quotes
+
+# The "scripts" lesson.
+
+##
+# Lesson 5: Testing Scripts
+##
+function bashunit::learn::lesson_scripts() {
+  clear
+  cat <<'EOF'
+╔════════════════════════════════════════════════════════════════╗
+║                 Lesson 5: Testing Bash Scripts                 ║
+╚════════════════════════════════════════════════════════════════╝
+
+CONCEPT: Scripts that execute commands directly are tested differently.
+Run them and capture their output.
+
+TASK: Create a script and test its output.
+
+File: greeter.sh (source code)
+───────────────────────────────────────────────────────────────
+#!/usr/bin/env bash
+name=${1:-World}
+echo "Hello, $name!"
+───────────────────────────────────────────────────────────────
+
+File: tests/greeter_test.sh (test file)
+───────────────────────────────────────────────────────────────
+#!/usr/bin/env bash
+
+function test_default_greeting() {
+  # TODO: Run greeter.sh from parent directory and capture output
+  # Hint: output=$(../greeter.sh)
+
+  # TODO: Assert output contains "Hello, World!"
+  # Hint: assert_contains "Hello, World!" "$output"
+}
+
+function test_custom_greeting() {
+  # TODO: Run greeter.sh with argument "Alice"
+  # Hint: output=$(../greeter.sh "Alice")
+
+  # TODO: Assert output contains "Hello, Alice!"
+  # Hint: assert_contains "Hello, Alice!" "$output"
+}
+───────────────────────────────────────────────────────────────
+
+TIPS:
+  • Use command substitution: output=$(./script.sh)
+  • Make scripts executable: chmod +x script.sh
+  • Test both default behavior and with various arguments
+  • Scripts run in subshells, so they can't modify parent environment
+  • Run scripts from parent directory: ../script.sh
+EOF
+
+  local default_file="tests/greeter_test.sh"
+  echo ""
+  printf "When ready, enter TEST file path %s[%s]%s: " \
+    "${_BASHUNIT_COLOR_FAINT}" "$default_file" "${_BASHUNIT_COLOR_DEFAULT}"
+  read -r test_file
+  test_file="${test_file:-$default_file}"
+
+  if [ ! -f "$test_file" ]; then
+    local template='#!/usr/bin/env bash
+
+function test_default_greeting() {
+  # TODO: Run greeter.sh from parent directory and capture output
+  # Hint: output=$(../greeter.sh)
+
+  # TODO: Assert output contains "Hello, World!"
+  # Hint: assert_contains "Hello, World!" "$output"
+}
+
+function test_custom_greeting() {
+  # TODO: Run greeter.sh with argument "Alice"
+  # Hint: output=$(../greeter.sh "Alice")
+
+  # TODO: Assert output contains "Hello, Alice!"
+  # Hint: assert_contains "Hello, Alice!" "$output"
+}'
+
+    bashunit::learn::create_example_file "$test_file" "$template"
+    return 1
+  fi
+
+  bashunit::learn::run_lesson_test "$test_file" 5
+}
+
diff --git a/src/learn/lessons/spies.sh b/src/learn/lessons/spies.sh
new file mode 100644
index 00000000..9e315b87
--- /dev/null
+++ b/src/learn/lessons/spies.sh
@@ -0,0 +1,121 @@
+#!/usr/bin/env bash
+
+# The "spies" lesson.
+
+##
+# Lesson 7: Spies
+##
+function bashunit::learn::lesson_spies() {
+  clear
+  cat <<'EOF'
+╔════════════════════════════════════════════════════════════════╗
+║              Lesson 7: Spies - Verifying Calls                 ║
+╚════════════════════════════════════════════════════════════════╝
+
+CONCEPT: Spies let you verify that functions were called with specific
+arguments or a certain number of times.
+
+KEY DIFFERENCE: Spies track calls without changing behavior, while
+mocks (Lesson 6) replace the function entirely with custom behavior.
+
+TASK: Use spies to verify function calls.
+
+File: deploy.sh
+───────────────────────────────────────────────────────────────
+#!/usr/bin/env bash
+
+function deploy_app() {
+  git push origin main
+  docker build -t myapp .
+  docker push myapp
+}
+───────────────────────────────────────────────────────────────
+
+File: deploy_test.sh
+───────────────────────────────────────────────────────────────
+#!/usr/bin/env bash
+
+function set_up() {
+  source deploy.sh
+}
+
+function test_deploy_calls_git_push() {
+  # TODO: Create spies for git and docker
+  # Hint: spy git
+  # Hint: spy docker
+
+  deploy_app
+
+  # TODO: Assert git was called
+  # Hint: assert_have_been_called git
+
+  # TODO: Assert docker was called
+}
+
+function test_deploy_calls_docker_twice() {
+  # TODO: Spy on docker
+
+  deploy_app
+
+  # TODO: Assert docker was called exactly 2 times
+  # Hint: assert_have_been_called_times 2 docker
+}
+───────────────────────────────────────────────────────────────
+
+TIPS:
+  • Spies track calls but don't change behavior (unlike mocks)
+  • assert_have_been_called - verifies at least one call
+  • assert_have_been_called_times N - verifies exact call count
+  • assert_have_been_called_with - verifies specific arguments
+  • Spies are cleaned up automatically after each test
+EOF
+
+  local default_file="deploy_test.sh"
+  echo ""
+  printf "When ready, enter TEST file path %s[%s]%s: " \
+    "${_BASHUNIT_COLOR_FAINT}" "$default_file" "${_BASHUNIT_COLOR_DEFAULT}"
+  read -r test_file
+  test_file="${test_file:-$default_file}"
+
+  if [ ! -f "$test_file" ]; then
+    local template='#!/usr/bin/env bash
+
+function set_up() {
+  source deploy.sh
+}
+
+function test_deploy_calls_git_push() {
+  # TODO: Create spies for git and docker
+  # Hint: spy git
+  # Hint: spy docker
+
+  deploy_app
+
+  # TODO: Assert git was called
+  # Hint: assert_have_been_called git
+
+  # TODO: Assert docker was called
+}
+
+function test_deploy_calls_docker_twice() {
+  # TODO: Spy on docker
+
+  deploy_app
+
+  # TODO: Assert docker was called exactly 2 times
+  # Hint: assert_have_been_called_times 2 docker
+}'
+
+    bashunit::learn::create_example_file "$test_file" "$template"
+    return 1
+  fi
+
+  if [ "$("$GREP" -c "spy" "$test_file" || true)" -eq 0 ]; then
+    echo "${_BASHUNIT_COLOR_FAILED}Your test should use spy${_BASHUNIT_COLOR_DEFAULT}"
+    read -p "Press Enter to continue..." -r
+    return 1
+  fi
+
+  bashunit::learn::run_lesson_test "$test_file" 7
+}
+
diff --git a/src/learn/menu.sh b/src/learn/menu.sh
new file mode 100644
index 00000000..b0067c18
--- /dev/null
+++ b/src/learn/menu.sh
@@ -0,0 +1,73 @@
+#!/usr/bin/env bash
+
+# The interactive menu and the top-level dispatch loop.
+
+##
+# Print the learning menu
+##
+function bashunit::learn::print_menu() {
+  cat <<EOF
+${_BASHUNIT_COLOR_BOLD}${_BASHUNIT_COLOR_PASSED}bashunit${_BASHUNIT_COLOR_DEFAULT} - Interactive Learning
+
+Choose a lesson:
+
+  ${_BASHUNIT_COLOR_BOLD}1.${_BASHUNIT_COLOR_DEFAULT} Basics - Your First Test
+  ${_BASHUNIT_COLOR_BOLD}2.${_BASHUNIT_COLOR_DEFAULT} Assertions - Testing Different Conditions
+  ${_BASHUNIT_COLOR_BOLD}3.${_BASHUNIT_COLOR_DEFAULT} Setup & Teardown - Managing Test Lifecycle
+  ${_BASHUNIT_COLOR_BOLD}4.${_BASHUNIT_COLOR_DEFAULT} Testing Functions - Unit Testing Patterns
+  ${_BASHUNIT_COLOR_BOLD}5.${_BASHUNIT_COLOR_DEFAULT} Testing Scripts - Integration Testing
+  ${_BASHUNIT_COLOR_BOLD}6.${_BASHUNIT_COLOR_DEFAULT} Mocking - Test Doubles and Mocks
+  ${_BASHUNIT_COLOR_BOLD}7.${_BASHUNIT_COLOR_DEFAULT} Spies - Verifying Function Calls
+  ${_BASHUNIT_COLOR_BOLD}8.${_BASHUNIT_COLOR_DEFAULT} Data Providers - Parameterized Tests
+  ${_BASHUNIT_COLOR_BOLD}9.${_BASHUNIT_COLOR_DEFAULT} Exit Codes - Testing Success and Failure
+  ${_BASHUNIT_COLOR_BOLD}10.${_BASHUNIT_COLOR_DEFAULT} Complete Challenge - Real World Scenario
+
+  ${_BASHUNIT_COLOR_BOLD}p.${_BASHUNIT_COLOR_DEFAULT} Show Progress
+  ${_BASHUNIT_COLOR_BOLD}r.${_BASHUNIT_COLOR_DEFAULT} Reset Progress
+  ${_BASHUNIT_COLOR_BOLD}q.${_BASHUNIT_COLOR_DEFAULT} Quit
+
+Enter your choice:
+EOF
+}
+
+
+##
+# Main learning loop
+##
+function bashunit::learn::start() {
+  bashunit::learn::init
+
+  trap 'bashunit::learn::cleanup' EXIT
+
+  while true; do
+    echo ""
+    bashunit::learn::print_menu
+    read -r choice
+    echo ""
+
+    case "$choice" in
+    1) bashunit::learn::lesson_basics || true ;;
+    2) bashunit::learn::lesson_assertions || true ;;
+    3) bashunit::learn::lesson_lifecycle || true ;;
+    4) bashunit::learn::lesson_functions || true ;;
+    5) bashunit::learn::lesson_scripts || true ;;
+    6) bashunit::learn::lesson_mocking || true ;;
+    7) bashunit::learn::lesson_spies || true ;;
+    8) bashunit::learn::lesson_data_providers || true ;;
+    9) bashunit::learn::lesson_exit_codes || true ;;
+    10) bashunit::learn::lesson_challenge || true ;;
+    p) bashunit::learn::show_progress ;;
+    r) bashunit::learn::reset_progress ;;
+    q)
+      echo "${_BASHUNIT_COLOR_PASSED}Happy testing!${_BASHUNIT_COLOR_DEFAULT}"
+      break
+      ;;
+    *)
+      echo "${_BASHUNIT_COLOR_FAILED}Invalid choice. Please try again.${_BASHUNIT_COLOR_DEFAULT}"
+      ;;
+    esac
+  done
+
+  bashunit::learn::cleanup
+}
+
diff --git a/src/learn/progress.sh b/src/learn/progress.sh
new file mode 100644
index 00000000..5cee5f5b
--- /dev/null
+++ b/src/learn/progress.sh
@@ -0,0 +1,71 @@
+#!/usr/bin/env bash
+
+# Lesson completion state, persisted in LEARN_PROGRESS_FILE.
+
+declare -r LEARN_PROGRESS_FILE="$HOME/.bashunit_learn_progress"
+
+##
+# Mark lesson as completed
+##
+function bashunit::learn::mark_completed() {
+  local lesson=$1
+  echo "$lesson" >>"$LEARN_PROGRESS_FILE"
+}
+
+
+##
+# Check if lesson is completed
+##
+function bashunit::learn::is_completed() {
+  local lesson=$1
+  [ -f "$LEARN_PROGRESS_FILE" ] && [ "$("$GREP" -c "^$lesson$" "$LEARN_PROGRESS_FILE" || true)" -gt 0 ]
+}
+
+
+##
+# Show learning progress
+##
+function bashunit::learn::show_progress() {
+  if [ ! -f "$LEARN_PROGRESS_FILE" ]; then
+    echo "${_BASHUNIT_COLOR_INCOMPLETE}No progress yet. Start with lesson 1!${_BASHUNIT_COLOR_DEFAULT}"
+    return
+  fi
+
+  echo "${_BASHUNIT_COLOR_BOLD}Your Progress:${_BASHUNIT_COLOR_DEFAULT}"
+  echo ""
+
+  local total_lessons=10
+  local completed=0
+
+  local i
+  for i in $(seq 1 $total_lessons); do
+    if bashunit::learn::is_completed "lesson_$i"; then
+      echo "  ${_BASHUNIT_COLOR_PASSED}✓${_BASHUNIT_COLOR_DEFAULT} Lesson $i completed"
+      ((++completed)) || true
+    else
+      echo "  ${_BASHUNIT_COLOR_INCOMPLETE}○${_BASHUNIT_COLOR_DEFAULT} Lesson $i"
+    fi
+  done
+
+  echo ""
+  echo "Progress: $completed/$total_lessons lessons completed"
+
+  if [ $completed -eq $total_lessons ]; then
+    echo ""
+    printf "%s%s🎉 Congratulations! You've completed all lessons!%s\n" \
+      "$_BASHUNIT_COLOR_PASSED" "$_BASHUNIT_COLOR_BOLD" "$_BASHUNIT_COLOR_DEFAULT"
+  fi
+
+  read -p "Press Enter to continue..." -r
+}
+
+
+##
+# Reset learning progress
+##
+function bashunit::learn::reset_progress() {
+  rm -f "$LEARN_PROGRESS_FILE"
+  echo "${_BASHUNIT_COLOR_PASSED}Progress reset successfully.${_BASHUNIT_COLOR_DEFAULT}"
+  read -p "Press Enter to continue..." -r
+}
+
diff --git a/src/learn/session.sh b/src/learn/session.sh
new file mode 100644
index 00000000..77127526
--- /dev/null
+++ b/src/learn/session.sh
@@ -0,0 +1,70 @@
+#!/usr/bin/env bash
+
+# The learning session's scratch directory and the runner that executes a lesson's example test.
+
+LEARN_TEMP_DIR=""
+
+##
+# Initialize learning environment
+##
+function bashunit::learn::init() {
+  LEARN_TEMP_DIR=$("${MKTEMP:-mktemp}" -d "${TMPDIR:-/tmp}/bashunit_learn.XXXXXXXX")
+  mkdir -p tests
+}
+
+
+##
+# Cleanup learning environment
+##
+function bashunit::learn::cleanup() {
+  if [ -n "${LEARN_TEMP_DIR:-}" ] && [ -d "$LEARN_TEMP_DIR" ]; then
+    rm -rf "$LEARN_TEMP_DIR"
+  fi
+}
+
+
+##
+# Create the example file automatically
+# Arguments: $1 - filename, $2 - file content
+##
+function bashunit::learn::create_example_file() {
+  local filename=$1
+  local content=$2
+
+  echo ""
+  echo "Creating example file ${_BASHUNIT_COLOR_BOLD}$filename${_BASHUNIT_COLOR_DEFAULT}..."
+  echo "$content" >"$filename"
+  chmod +x "$filename"
+  echo "${_BASHUNIT_COLOR_PASSED}✓ Created $filename${_BASHUNIT_COLOR_DEFAULT}"
+  echo ""
+  echo "File created! Edit it to complete the TODO items, then run this lesson again."
+  read -p "Press Enter to continue..." -r
+  return 0
+}
+
+
+##
+# Run a lesson test and check results
+##
+function bashunit::learn::run_lesson_test() {
+  local test_file=$1
+  local lesson_number=$2
+
+  echo "${_BASHUNIT_COLOR_BOLD}Running your test...${_BASHUNIT_COLOR_DEFAULT}"
+  echo ""
+
+  if "$BASHUNIT_ROOT_DIR/bashunit" "$test_file" --simple; then
+    echo ""
+    printf "%s%s✓ Excellent! Lesson %s completed!%s\n" \
+      "$_BASHUNIT_COLOR_PASSED" "$_BASHUNIT_COLOR_BOLD" "$lesson_number" "$_BASHUNIT_COLOR_DEFAULT"
+    bashunit::learn::mark_completed "lesson_$lesson_number"
+    read -p "Press Enter to continue..." -r
+    return 0
+  else
+    echo ""
+    echo "${_BASHUNIT_COLOR_FAILED}Not quite right. Review the requirements and try again.${_BASHUNIT_COLOR_DEFAULT}"
+    read -p "Press Enter to continue..." -r
+    return 1
+  fi
+}
+
diff --git a/tests/unit/learn_test.sh b/tests/unit/learn_test.sh
index 775a490c..b8f6df25 100644
--- a/tests/unit/learn_test.sh
+++ b/tests/unit/learn_test.sh
@@ -1,9 +1,9 @@
 #!/usr/bin/env bash
 set -euo pipefail
 
-# Covers the non-interactive core of src/learn.sh: progress persistence and the
-# environment lifecycle. LEARN_PROGRESS_FILE is a readonly resolved from $HOME at
-# source time, so each test sources learn.sh in a fresh shell with HOME pointed
+# Covers the non-interactive core of the src/learn/ module: progress persistence
+# and the environment lifecycle. LEARN_PROGRESS_FILE is a readonly resolved from
+# $HOME at source time, so each test sources the module in a fresh shell with HOME
 # at an isolated directory — the suite's own already-sourced copy (bound to the
 # real $HOME) is never exercised.
 
@@ -26,14 +26,14 @@ function _learn_in_sandbox() {
         BASHUNIT_ROOT_DIR="'"$root_dir"'"
         export BASHUNIT_ROOT_DIR
         GREP="$(command -v grep)"
-        # learn.sh renders coloured output but does not source colors.sh. Stub
+        # learn renders coloured output but does not source colors.sh. Stub
         # the palette to empty rather than pulling in the real chain
         # (str -> globals -> env -> colors), which would couple this unit test to
         # source order and make the assertions match escape codes.
         _BASHUNIT_COLOR_BOLD="" _BASHUNIT_COLOR_DEFAULT="" _BASHUNIT_COLOR_FAILED=""
         _BASHUNIT_COLOR_FAINT="" _BASHUNIT_COLOR_INCOMPLETE="" _BASHUNIT_COLOR_PASSED=""
         # shellcheck source=/dev/null
-        source "'"$root_dir"'/src/learn.sh"
+        source "'"$root_dir"'/src/learn/index.sh"
         '"$1"'
       ' </dev/null
   )