Semi-Magic Squares

Semi-Magic Squares

Semi-magic squares are thought of as matrices in this arithmetic exploration. Split up a a shuffled deck of cards to create a magic-square out of playing cards with additional challenges. Submitted by: James Tanton Time Required: 30 minutes You’ll Need: paper, pencil,...
A Better Mousetrap

A Better Mousetrap

A Better Mousetrap is three-part topological effect from Magician Michael Weber, in which part of a 5×7 index card seems to magically pass from one side of a spectator’s hand to the other, while their eyes are closed! How to...