Premium lessons and video export.

Early-supporter price $29. Regular price $49. One-time payment.

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Complete lessons, no account needed to start.

  • Every free lesson, complete — player, quiz, and sandbox
  • The Explain doc on every lesson, premium included
  • Scrub, step, and replay the trace
  • Type your own input on any lesson
  • Share links, embeds, and watermarked PNG export
  • Progress, bookmarks, and saved inputs kept in this browser
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$49regular price
$29early-supporter price · one-time

Everything in Free, plus:

  • Every premium lesson in this catalog unlocked
  • Advanced algorithms, AI, and computer systems
  • Future premium lessons added to this catalog
  • Video export, without a watermark
  • Watermark-free PNG export
  • Progress, bookmarks, and saved inputs synced across devices

72 premium lessons, one purchase.

Choose a lesson to preview its player or read the free Explain doc. Lifetime includes every lesson below and future premium additions to this catalog.

AlgorithmPremium lessons: 24

AIPremium lessons: 28

Computer SciencePremium lessons: 20