What are your Math Puzzle Challenges?

The classic card game of Proof!, now in the form of math puzzles.

The Proof! tabletop card game is the inspiration behind our free, online math game, the Math Puzzle Challenges. To up the anty, we've created over 300 brain-bending puzzles that each look like a regular game of Proof!, but where the nine cards hide a challenging equation. Can you solve them all?