Unequal: The Math of When Things Do and Don’t Add Up

To Sleep in a Sea of Stars (Fractalverse)

How to Solve It: A New Aspect of Mathematical Method (Princeton Science Library)

Quantum Mechanics: The Theoretical Minimum

MATH OLYMPIAD CONTESTS PREPARATION GRADES 4-8: AMC-8, MATHCOUNTS, MATHCON,& MATH LEAGUES

The Language Lover’s Puzzle Book: A World Tour of Languages and Alphabets in 100 Amazing Puzzles (Alex Bellos Puzzle Books)

The Joy Of X: A Guided Tour of Math, from One to Infinity

The Book of Why: The New Science of Cause and Effect

Infinite Powers: How Calculus Reveals the Secrets of the Universe

Pre-Algebra Skills: (Grades 6-8) Middle School Math Workbook (Prealgebra: Exponents, Roots, Ratios, Proportions, Negative Numbers, Coordinate Planes, ... & Statistics) – Ages 11-15 (With Answer Key)