Mental Arithmetic Book 6: KS2 Maths, Years 6, Ages 10-11 it has been written in with pencil until page 4 but otherwise good Mental Arithmetic 6 extends beyond the Key Stage 2 curriculum,consolidating key subject areas alongside more advanced concepts. The book includes: 36 one-page tests, each presented in a unique three-part format comprising: questions on number, calculation and algebra, questions on money, measurement, geometry and approximations, longer problem-solving questions.