Abstract
"Astronomy education researchers now know that college students do not enter the introductory astronomy classroom as blank slates, but rather these students enter the classroom with a pre-existing understanding of m any introductory astronomy concepts, including lunar phases. Sometimes this understanding is scientifically correct, b u t often students' understanding is incomplete, inadequate or simply incorrect and cannot explain observed phenomenon. Unfortunately, students' pre-existing understandings are often deeply rooted, and m any students leave the classroom without a scientifically correct understanding of lunar phases. The question now arises, how do instructors develop successful instruction so that students leave the classroom with a scientifically correct understanding of lunar phases? The purpose of this research study was therefore to design instruction that enhances college students’ understanding of lunar phases. This multi-phase study utilized both qualitative and quantitative research methods to fulfill this purpose by identifying students’ prior understanding of lunar phases, developing the Lunar Phases Concept Inventory (LPCI) to measure conceptual change, designing and evaluating an in-class group activity designed to teach the concept of lunar phases.
Using a qualitative phenomenology, fourteen college students’ conceptual understanding of lunar phases was uncovered. This conceptual understanding was organized into a conceptual framework with eight separate dimensions of student understanding, each with alternative facets of student understanding. Based upon this conceptual framework, the LPCI was developed. This instrument consists of fourteen multiple-choice items designed to assess student understanding of lunar phases.
Based on a modified Karplus Learning Cycle, an in-class group activity was developed to teach the concept of lunar phases. During the fall semester of 1999, this activity was implemented a t a midwestem university as part of a restructured astronomy course. This activity took only two fifty-minute class periods. Administered prior to and after instruction, the LPCI shows that the instruction was indeed effective. A statistical analysis of the results shows that the instruction produced an effect size of 2.99 and a normalized gain of 0.63."
