My book is the Time Life book on Mathematics. I read it when I was 10. The description of Calculus mesmerized me. I became a math professor and taught Calculus for more than 30 years.
#mathsky

Such a great book and (no spoilers) the ending is perfect.

One Hit Wonder by Lisa Jewell in English, La Sinfonía de Julia by Mercedes Guerrero in Spanish. Just finished The Honey Bus by Meredith May. Highly recommend it.