Do the Math!: Challenging, Fun Math Puzzles for Kids by Steven Clontz and Jessica Clontz, Kids ages 8 to 12 will build there core math skills needed to succeed in school and beyond_all while having fun! This awesome collection of interactive activities include cryptograms waiting to be decoded, or even a sodoku that needs to be solved. Each puzzle type starts simple and gets harder as they go along. Paperback, 142 pages. Recommended for ages 8 to 12 years old.