AN ATTEMPT TO IMPROVE THE RELIABILITY, VALIDITY, AND EFFICIENCY OF ALL READING INSTRUCTION BY MODIFYING CERTAIN DIMENSIONS OF TEACHER BEHAVIOR IS REPORTED. A SURVEY IN OREGON INDICATED THAT TO DETERMINE THE FUNCTIONAL READING LEVEL OF STUDENTS, 74 PERCENT OF THE TEACHERS USED GRADE EQUIVALENT SCORES FROM ACHIEVEMENT TESTS, 24 PERCENT USED INFORMATION FROM CUMULATIVE FOLDERS, AND 30 PER CENT USED COMBINATIONS. MATERIALS WERE DEVELOPED TO GIVE PROSPECTIVE TEACHERS AN OPPORTUNITY TO LEARN THE MARKING CODE OF THE INFORMAL READING INVENTORY, TO PRACTICE, AND TO EVALUATE THEIR SKILL. A SERIES OF SIMULATED INSTRUCTIONAL FILMS AND PRINTED MATERIALS WAS DEVISED. THE PROCESS EXPERIENCED BY THE TEACHERS IN THREE CLASS PERIODS IS DESCRIBED. ONE HUNDRED UNDERGRADUATE STUDENTS WERE STUDIED TO DETERMINE THE EFFICIENCY OF THE MATERIAL. THE RESULTS INDICATED THAT TEACHERS, AFTER VIEWING SIMULATED MATERIAL, WERE 92 PERCENT ACCURATE IN ASSESSING FUNCTIONAL READING LEVEL. AFTER REVISION OF THE MATERIAL, A SECOND STUDY WAS CONDUCTED WITH 50 SUBJECTS. THE RESULTS INDICATED 94 PERCENT ACCURACY. A DISCUSSION OF TRANSFER INTO ACTUAL CLASSROOM PRACTICE AND REFERENCES ARE INCLUDED. (BK)