The broad cognitive abilities defined by the Cattell-Horn-Carroll (CHC) theory have been shown to predict school achievement. However, the ecological validity of these constructs has not been studied in classroom settings. This study compares ratings by a sample of teachers (n = 53) and school psychologists (n = 86) of the importance of the CHC cognitive abilities in the classroom. The scale demonstrated adequate reliability (total scale alpha = 0.93, median alpha = 0.74), although evidence of construct validity varied between teachers and school psychologists. Both teachers and school psychologists rated quantitative ability, crystallized knowledge, and fluid reasoning as most important to school success. However, school psychologists rated short-term memory and quantitative ability as more important than did the teachers. Importance of these differences for consultation is discussed. (Contains 5 tables and 1 figure.)