Skip to main content

Welcome, you are visiting PRISM

PRISM Library

Elementary Teachers' Understanding of Standards-Based Light Concepts Before and After Instruction


A descriptive study conducted to investigate how the pre-instruction and post-instruction conceptual understanding of inservice elementary teachers compare on: 1) light travels in a straight line until it strikes an object; 2) light is reflected in a predictable manner by a plane mirror; and, 3) refraction changes the straight line path of light in predictable ways. Because interviews were impossible, ten multiple choice tasks with alternative conceptions embedded in distracter options were utilized to assess the conceptual understanding of 72 teachers from rural school districts in three Mid-Atlantic States. Results are discussed by task in the paper. Pretest performance ranged from 8.3% to 75.0% correct responses on the ten tasks and 49.3% to 90.1% on posttest. The strong improvement across all tasks is attributed to the utilization of evidence-based instructional materials (McDermott, 1996) that promote intentional learning. While the results suggest most teachers made substantial progress in constructing a logically consistent and scientific model of the targeted light phenomena, further improvement is desirable and should be possible by using the data for formative purposes.