Math Games with Bad Drawings: 75 1/4 Simple, Challenging, Go-Anywhere Games―And Why They Matter

The Ultimate Activity Book for Awesome Engineers: Tricky Brain Teasers, Mind Games and Logic Puzzle Book for Smart Adults (Perfect Gift for Engineers)

Brain Teasers for Smart Engineers: Tricky Brain Twisters, Mind Games and Fun Problem Solving for Engineers (Perfect Gifts for Engineers)

The Hardest Logic Workbook for Gritty Kids: Spatial Reasoning, Math Puzzles, Word Games, Logic Problems, Focus Activities, Two-Player Games. (Develop ... & STEM Skills in Kids Ages 10, 11, 12.)

Of Course!: The Greatest Collection of Riddles & Brain Teasers For Expanding Your Mind

Sudoku Puzzles for Adults: 1000+ Puzzles Easy to Hard with full Solutions

Absolutely Nasty® Kakuro Level Three (Absolutely Nasty® Series)

Sharp Minds for Seniors: The Ultimate Puzzle Book for Retirees to Boost Memory, Increase Cognitive Abilities and Have Fun with Brain Games and Activities (The Perfect Gift)

The Colossal Book of Mathematics: Classic Puzzles, Paradoxes, and Problems

Sudoku for Kids Ages 10-12: Over 200 Puzzles | Easy Medium & Hard