Cognitive clusters from the Woodcock-Johnson III (WJ III) Tests of Cognitive Abilities that measure select Cattell-Horn-Carroll broad and narrow cognitive abilities were shown to be significantly related to mathematics achievement in a large, nationally representative sample of children and adolescents. Multiple regression analyses were used to predict performance on the Math Calculation Skills and Math Reasoning clusters from the WJ III Tests of Achievement for 14 age groups ranging in age from 6 to 19 years. Comprehension-Knowledge (Gc) demonstrated moderate relations with Math Calculation Skills after the early school-age years and moderate to strong relations with Math Reasoning. Fluid Reasoning (Gf), Short-term Memory (Gsm), and Working Memory generally demonstrated moderate relations with the mathematics clusters. Processing Speed (Gs) demonstrated moderate relations with Math Reasoning during the elementary school years and moderate to strong relations with Math Calculation Skills. During the earliest ages of the analysis, Long-term Retrieval (Glr) demonstrated moderate relations with the mathematics clusters, and Auditory Processing (Ga) demonstrated moderate relations with Math Calculation Skills. Visual-Spatial Thinking (Gv) generally demonstrated nonsignificant relations with the mathematics clusters. (Contains 4 footnotes, 3 tables, and 4 figures.)