The Woodcock-Johnson Tests of Achievement (WJ ACH) is a comprehensive, standardized, norm-referenced set of tests used to assess academic skills [Page 1746]across the major areas of reading, writing, and math and to evaluate knowledge of science, social studies, and humanities. The WJ ACH is commonly used in a variety of professional contexts, including the assessment and diagnosis of intellectual and developmental disabilities. Individuals with intellectual and developmental disabilities often demonstrate impairment in academic achievement, including decreased performance on the WJ ACH.

This entry discusses the history and theoretical basis of the WJ ACH. It then describes the WJ ACH and highlights several main features of the test, such as how many and what types of subtests it includes. Next, it describes common uses of the WJ ...