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PyTrail Interactive Review

PyTrail has 150 interactive "levels" that review the course week by week. Each level has a short lesson and a task.

Open PyTrail

Saving your progress

PyTrail saves your progress only in the browser you are using. Keep a copy of your progress in your git repository, so that you don't lose your work and can use another computer:

  1. In PyTrail, click Progress, then Download progress file.
  2. Move the file pytrail.json into your ~/CS149 folder, and replace the old file. If your browser named the file pytrail (1).json or similar, rename the file to pytrail.json.
  3. Commit and push pytrail.json.
  4. On another computer, run git pull. Then, in PyTrail, click Progress → Load a progress file, and choose ~/CS149/pytrail.json.

When your instructor asks, upload pytrail.json to PyTrail Progress on Gradescope.

Suggested pace

We recommend you work on PyTrail during the last five weeks of the course. Finish the chapters below by each Friday, and finish all the levels by the last day of classes. Then your Toolbox will be complete when you study for the final exam.

By Chapters Levels Total Score
Fri, Nov 6 13–15 25 25 33
Fri, Nov 13 16–19 34 59 79
Fri, Nov 20 1–4 32 91 121
Fri, Dec 4 5–9 31 122 163
Fri, Dec 11 10–12, 20 28 150 200

The chapters are not in order. Chapters 13–15 review while loops, sets, and string methods for Quiz 4. Chapters 16–19 review files, dictionaries, comprehensions, and nested data for Quiz 5. To start a chapter, open the Levels menu and click the chapter's first level. (The Continue button always goes to the next level in order.)