The Effect of Four-Component Instructional Design Model on Extraneous Cognitive Load and Problem-Solving Skills in Physics Course

This study aimed at determining the effect of four-component instructional design model on the extent of extraneous cognitive load and problem-solving skills in physics course. The study was quasi-experimental using pre-test, and post-test with experimental and control groups. The population of the study included all first-grade high-school male students of the 5th region in Tehran during 92-93 school year. The sample of the study was selected using multi-level clustered random sampling and included 30 students who were randomly placed in an experimental group (n = 15) and a control group (n = 15). The experimental group underwent a treatment (instructional design of the physics course based on the four-component model) and the control group was instructed using the traditional method. One instrument for gathering the data was Pass (1992) 9- rating scale, the face validity of which was judged by the experts and professors and its reliability was examined using Test-Retest method and turned out to be 0.85. The other instrument was a researcher-made problem-solving skills test. The face validity of the test was judged by expert views and test-retest method showed the reliability of the test as 0.79. An independent t­-test (for determining extraneous cognitive load) and ANCOVA (for a problem-solving skills test) were used to analyze the data. The results of the study indicated that four-component instructional design model had a significant effect on decreasing extraneous cognitive load in the experimental group in comparison with the control group (p>.00). Also, the results showed a significant increase in the extent of problem solving skills for the experimental group in comparison with the control group (Partial Eta Squared = 0.14, F = 4.34, p