This investigation was an attempt to determine the suitability of a highly structured course in science, Introductory Physical Science (IPS), for all eighth-grade students in a suburban school. The major measure for the evaluation of the course was to study the degree of teacher commitment to the objectives of the course and determine if this influenced the students' mastery of content and perception of science as measured by the Test on Understanding Science (TOUS). Twelve teachers with one randomly selected class per teacher provided a sample of three hundred students. Pre- and post-tests were administered to all. The tests were a summary IPS Achievement Test and TOUS, Jx. Teachers were ranked using data from a Classroom Activity Checklist administered at the end of the year. Analysis was made relevant to what influence the degree to which a teacher's ability to use IPS ideally had on his students' achievement and understanding of science. A positive relationship was discovered. Student academic ability had some significant effect. It was concluded that IPS did not produce significant change in students' perception of the nature of science as measured by the TOUS, Jx and is not flexible enough for a very wide range of student abilities. (Author/EB)