Skip to the main content

The print edition is coming.

The same 308 problems, nudges and answers, in print. Worked solutions stay online and are free with your copy: one question from the book unlocks them.

Was $45, now $35Founding price.

Leave your email and I will tell you when it opens.

Volume I, front cover

Prefer paper?

Volume I, in print.

The same 308 problems, with the four to five layered nudges and the answers, printed and in your hands. No screen, no battery, and you can write on it.

Worked solutions stay online and are free with your copy. One question from the book unlocks them, so they follow the object rather than a receipt.

In the meantime

22 of the 308 are open right now, spread across the set. Same stem, same nudges, same worked solution as the paid ones.

Read the free problemsAlready bought? Sign in