This study evaluated the effect of a comprehensive training program for teachers based on Madeline Hunter's Instructional Theory Into Practice (ITIP). To examine the question of implementation, teachers in the first through fourth grades in Napa Valley elementary schools were observed teaching two reading and two mathematics classes before and after trainng. Program implementation was measured using the Instructional Skills Observation Instrument (OSOI) which rated how well the teacher: (1) provided a set of focus for the lesson; (2) provided instruction; (3) directed guided practice; and (4) monitored independent practice. A description is given of the comprehensive inservice training sessions on implementing these four components of the Hunter ITIP. The major questions of the study focused upon the relationship between teacher implementation of the Instructional Skills Program, student engaged rates, and student achievement. Findings indicated that over a two-year period higher achievement in both mathematics and reading was evident in the performance of students of teachers with the higher OSOI ratings. An analysis of the results includes consideration of other factors which may have influenced student outcomes. One finding in particular is noted: children with limited English speaking skills benefitted from the program. Statistical data on the study are presented in tabular format. (JD)