Challenging Students Ideas About Earth's Interior Structure Using a Model-based, Conceptual Change Approach in a Large Class Setting

Abstract

A model-based, conceptual change approach to teaching was found to improve student understanding of earth structure in a large (100+ student) inquiry-based, general education setting. Results from paired pre- and post-instruction sketches indicated that 19% (n = 18/97) of the students began the class with naïve preconceptions of the structure of the interior of the Earth. Many of the remaining students (95%; n = 75/79) began the lesson believing that the crust is several hundred kilometers thick. Peer discussion and instruction appeared to be effective in eliminating most naive preconceptions. Analyses of post-instruction sketches indicated that 3% (n = 3/97) of all students retained naïve preconceptions, 18% (n = 18/97) changed their views from naïve to the “thick crust” view, 58% (n = 58/97) began to recognize the relative scales of the boundaries with 30% (n = 28/97) drawing the sketch with scaled boundaries. Many of the students (65%; n = 76/117) could correctly answer formative earth structure conceptual questions that were asked five lessons after the earth structure lesson was taught. A comparison of pre- and post-course conceptual test question responses indicated that 13–20% more students could correctly answer similar questions two months after the model-based, conceptual change plate tectonics lessons were taught.