Learn to Subtract 8 from Numbers 8-20 This book includes one new subtraction fact every day, (32 pages, 40 daily problems, 14 days of practice, 550 problems per book, 6,500+ per series), handwriting aids, cumulative practice, daily achievements stars, and a completion certificate. Perfect for students in grades 1-4, ages 6+, who have mastered Addition. Learning Objectives: Subtraction proficiency and fluency, legible handwriting, number sense, and independent learning. For Best Results: Use this book in conjunction with all the books in the Page A Day Math Subtraction 13-book series. Math is fun with Page A Day Math books and the encouraging Math Squad, Mo, Zo, Bo, Flo and Jo. Children and parents love math with the Math Squad!