Using the Component Display Theory as an analyzing tool, this study compared the effects of expository and discovery methods of instruction on two learning outcomes, application and transfer. One hundred ninth grade students in each of four earth science classes were randomly assigned to five groups--four experimental groups designed to test four instructional sequences and a control group. The sequences investigated were: (1) GEPG, i.e., a generality at the beginning of a lesson, followed by examples and practice exercises, and ending with a restatement of the generality (expository); (2) EP, i.e., examples followed by practice (discovery); (3) GEP, i.e., a generality first, followed by examples and then practice (expository); and (4) EPG, i.e., examples followed by practice and ending with a generality (discovery). A posttest-only control group served as the experimental design. The four treatment groups received different versions of a lesson on the concept and two basic principles of plate tectonics. Each student was given a lesson booklet and a separate booklet of figures and maps as study aids, and learning was self-paced. At the end of the lesson, they were expected to transfer this knowledge to a different situation by generating a new but related principle. Data from the 39 students who completed the activity were analyzed using analysis of variance and a 2 x 2 factorial design. No significant differences were found among the groups for either application or transfer learning, although partial support was found for one of the three hypotheses tested. (RP)