A system designed to provide a framework for the individualization of reading instruction is discussed. The heart of the system is a mastery checklist of reading skills for each child which provides teachers with a means for discovering the specific skill needs of their students. Initially, the system depended upon individual assessment exercises as the main source of specific skill measurement, but because the administration of these exercises was not an efficient use of time, work began on group assessment exercises designed to test the same skills. A discussion of the construction, format, and revision of these group prototypic assessment exercises measuring word attack, comprehension, and study skills is presented, and it is noted that information from the exercises provides a basis for appropriate choices of instructional approaches and of materials for each student. Sample exercises and checklists are provided. One reference is included. (RT)