Date of Award


Level of Access Assigned by Author

Open-Access Thesis

Degree Name

Master of Science (MS)




Stephen A. Norton

Second Committee Member

Peter O. Koons

Third Committee Member

John R. Thompson


Density is an important physical concept in all of science. Substantial education research on the teaching and learning of density has occurred in physics, chemistry, and biochemistry; there has been little education research about density in the earth sciences. This study investigates the extent to which targeted instruction influences student understanding of density, and the frequency and accuracy with which students apply it in explanations of earth science phenomena. All data for the study were collected from students in The Environmental Geology of Maine (ERS 102) at the University of Maine during the spring and fall 2004 and spring 2005 semesters. Responses to three earth science-related post-course questions, from the final examination in spring 2004, served as baseline data for the study (n = 66), as well as a trial run for assessment questions. Based on the fall 2004 data, a pre-/post-course assessment on density was developed for targeted instruction. The assessment contained three questions about density in an earth science setting, and seven more general questions on mass, volume, and density. The targeted instruction was implemented for two experimental groups (ntotal = 97) in fall 2004 and spring 2005. The pre-course assessment determined students’ prior knowledge and understanding of the concept of density upon entering the class. An inquiry-based laboratory exercise, focused on density, was designed for use as the intervention in both experimental groups. The exercise centered on students determining the density of homogeneous and heterogeneous substances. The post-course assessment, identical to the pre-course assessment, measured students’ understanding and performance after the new density exercise. Chi-squared analyses of pre-/post-course assessment results for both experimental groups revealed three findings: (1) responses to approximately one third of assessment questions improved; (2) responses to approximately one third of assessment questions remained consistent or showed some decline in level of understanding; and (3) responses to approximately one third of assessment questions had insignificant differences. Overall, the density laboratory exercise appears to have positively influenced student understanding of density in and out of an earth science context, as measured by the pre- /post-course assessment. However, there is much room for revision to both research instruments.