Tried and True Children's Learning Books

Mathematics

The Grapes Of Math

Go Figure!: A Totally Cool Book About Numbers (Bccb Blue Ribbon Nonfiction Book Award (Awards))

Math For All Seasons: Mind-Stretching Math Riddles (Scholastic Bookshelf)

Math Curse

The Boy Who Loved Math: The Improbable Life of Paul Erdos

Millions, Billions, & Trillions: Understanding Big Numbers

Science

What's Smaller Than a Pygmy Shrew? (Wells of Knowledge Science)

The Flash's Book of Speed (DK READERS)

Things That Float and Things That Don't  

Air Is All Around You (Let's-Read-and-Find-Out Science 1)

How to Be a Genius

Robotics: DISCOVER THE SCIENCE AND TECHNOLOGY OF THE FUTURE with 20 PROJECTS (Build It Yourself)

History

A Little History of the World

A Little History of the World: Illustrated Edition (Little histories)