Readers use simple addition, subtraction, multiplication, and division to solve equations about skeletons, ravens, bats and other spooky friends. "An entertaining and effective math primer."—Publishers Weekly
4.OA.A.3 Solve multistep word problems posed with whole numbers and having whole-number answers using the four operations, including problems in which remainders must be interpreted. Represent these problems using equations with a letter standing for the unknown quantity. Assess the reasonableness of answers using mental computation and estimation strategies including rounding.