You Can Count on Monsters Richard Evan Schwartz A K Peters, $24.95, 244 pages (paperback), ages 4-8 Math is no monster in the clever hands of Richard Evan Schwartz, a math professor at Brown University. With logic and oodles of humor, he makes primes and composites perfectly clear. (A composite number is the product of two primes.) After explaining and illustrating the basic concept with dots and number trees, he goes on to illustrate each number to 100. Each prime number also gets a funky and colorful monster, since it can't have a number tree. Schwartz created his ingenious paperback, subtitled “The First 100 Numbers and Their Characters,” for his young daughter. Reviewed Jan. 22 on National Public Radio by “Math Guy” Keith Devlin, this charming book from an academic publisher took off like a rocket. ————————— Judy Green can be reached at jgreen@sacbee.com.