For instructional materials to be certified as "effective," students must meet instructional objectives operationalized by criterion tests. By implication, evaluators must agree when criteria are or are not met. Fourteen instructors evaluated 10 posterior bridges. Interjudge agreements for total bridges and individual attributes were low, as they tend to be whenever dental technic products are evaluated. A method for developing more reliable rating forms is described. It consists of: (1) limiting discriminations to the dichotomous decision "acceptable", "unacceptable"; (2) initially resolving differences among faculty; and (3) defining characteristics of acceptability on observable terms, and providing a photographic example of a minimally acceptable product for each attribute. (Author)