Art of Problem Solving Middle School Blue 7-Book Set # 2 : AoPS Introduction to Counting and Probability 2-Book Set : A thorough introduction for students in grades 7-10 to counting and probability topics such as permutations, combinations, Pascal's triangle, geometric probability, basic combinatorial identities, the Binomial Theorem, and more. AoPS Introduction to Geometry 2-Book Set : A full course in challenging geometry for students in grades 7-10, including topics such as similar triangles, congruent triangles, quadrilaterals, polygons, circles, funky areas, power of a point, three-dimensional geometry, transformations, introductory trigonometry, and more. AoPS Introduction to Number Theory 2-Book Set : A thorough introduction for students in grades 7-10 to topics in number theory such as primes & composites, multiples & divisors, prime factorization and its uses, base numbers, modular arithmetic, divisibility rules, linear congruences, how to develop number sense, and more. The Seventh Book is a Surprise Horrible Book from the Horrible Books Humorously Educational Series that covers Math, Science, Geography, History, and Biography that will totally complement your child's love for learning. Horrible Ray endorses the Art of Problem Solving Middle School Green 5-Book Set # 1 for Grades 7-10.