Mathematical Practice: MP1

Frogs can only move right, or down, and toads can only move left, or up. Can you exchange all the frogs and toads? Can you create a formula for the fewest number of moves? This deceptively simple puzzle starts with a row of frogs and toads, then advances to a grid. The game can be played with manipulatives, online, or even with people to provide an engaging, solitary or cooperative activity for all ages.

Your goal is the place the numbers 1 – 9 in a 3 by 3 grid so each row, column, and diagonal add up to the same magic number. Can you find what this magic number is?