USING THE GCI TO EVALUATE STUDENT LEARNING IN INTRODUCTORY GEOSCIENCE COURSES THAT USE CONCEPTESTS TO PROMOTE PEER LEARNING

The use of conceptests during introductory geology lectures add a component of active peer learning to an otherwise passive learning environment. Peer learning has been shown to increase student mastery of important concepts taught during these classes. Conceptests have been used in introductory geology classes (Introduction to Geology and Environmental Geology) at Muskingum College since the Fall 2003 semester. The introductory geology classes are typically taught as double sections having a maximum class limit of 48 students. Starting with the Fall 2005 semester a 15-question GCI (Geoscience Concepts Inventory) test has been given during the first week of class and the test is repeated during the final week of classes to assess student gains in knowledge. We also administer the GALT (Group Assessment of Logical Thinking) exam during the first and final week of the semester.

The results from the Fall and Spring 2005 semesters are mixed. Libarkin and Anderson (2005) report a mean of 42.2 percent for the GCI pre-test given to approximately 1500 students in diverse settings with different class sizes and lecture styles across the country and a post-test mean of 45.8 percent (approximately 1300 students). We recorded a pre-test mean of 41.1 percent and a post-test mean of 46.1 percent for the Fall 2005 Introduction to Geology class (41 students). These results are very similar to Libarkin and Anderson (2005). In contrast the Spring 2005 Environmental Geology class (36 students) recorded a pre-test mean of 35.1 percent and a post-test mean of 47.5 percent. This would appear to represent a significant increase in conceptual understanding. The average pre-GALT score for the Fall 2005 class was 7.3 and was 6.64 for the Spring 2005 class. The other difference between the two classes revealed by the GALT exam is that the Fall 2005 class had a higher proportion of formal thinkers (39.0 percent) compared to the Spring 2005 class (22.2 percent). Also there was a slightly higher percentage (16.7 compared to 14.7) of the Spring 2005 class had no exposure to Earth Science in high school. In conclusion, although the results are mixed they may indicate that conceptests may more impact on classes that are less prepared and have more students that have never been formally exposed to Earth Science than for classes that are academically more prepared.