> ## Documentation Index
> Fetch the complete documentation index at: /help/llms.txt
> Use this file to discover all available pages before exploring further.

# Courses and lessons

> Work through structured vocabulary lessons.

Courses organize vocabulary into structured lessons with guided practice and progress tracking.

**1. Open Courses and browse the available course stacks**

**2. Choose a course to view its units, lessons, and word coverage**

**3. Open an available lesson and review its introduction**

**4. Complete Practice 1 and Practice 2 when they are available**

**5. Finish the lesson to record your progress and score. You can redo earlier lessons to improve your results.**

## What mastery levels mean

Each word in a lesson is tracked at one of five mastery levels, based on how often you've practiced it, how accurate you've been, and whether that practice is spread across multiple sessions and days. Unseen means you haven't practiced the word yet. Learning means you've started practicing but haven't yet built up enough correct, consistent answers. Familiar means you've gotten a handful of reps in and are answering correctly most of the time. Strong means you've practiced the word across at least two separate sessions and are consistently getting it right. Mastered means you've reinforced the word over at least three sessions on at least two different days, including at least one answer you produced yourself — like typing or spelling it — rather than picking from options.

> [!NOTE]
>
> **Course progress**
>
> Lesson progress, session scores, and course scores are tied to your signed-in account. Use the same account on each device to keep progress together.


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