As schools return to session, some of us may regret all that we have learned - and lost. “Homework for Grown-ups: Everything You Learned at School and Promptly Forgot’’ by E. Foley and B. Coates (Broadway) fills the gaps in nine subjects, ranging from math to literature, science to art. Each chapter ends with a test; answers are provided at the back of the book. You’ll find the Pythagorean theorem; the Fibonacci sequence; types of clouds, dinosaurs, and architectural styles; the Bill of Rights; and the periodic table. It’s a rather classical education - except for the lesson about how to survive a nuclear attack.