Specified procedures for evaluating materials during their in-context tryout are presented. These procedures deal with all possible causes of system failures that have been identified in the in-classroom tryout of new materials. Therefore, methods for identifying, controlling, and monitoring all factors that affect academic behavior in the classroom are described. This includes (1) the definition of classroom management rules and ways to monitor their effectiveness, (2) the collection of objective and subjective data to discover weaknesses in both the materials and the classroom environment, and (3) the ways to systematically evaluate the effectiveness of all changes made to the environment. Testing procedures were also defined. They included where to take a test, how to take a test, and how to score the test. Test performance was used to locate inadequate materials and to evaluate revised materials. Systematic formative evaluation during the in-context tryout of materials was shown to be feasible. (Author/DB)