In an effort to increase effective learning in an introductory Earth Science course, various pedagogical modifications were introduced to the curriculum. Tracking changes in grade averages and class retention rates over time permits assessment of the effectiveness of specific modifications on students’ content knowledge and interest.

The class is a non-lab course intended to accommodate the general education science requirement of career curricula students at the community college level. A typical class includes students with diverse academic skills; there are no prerequisites and the only recommendation is that students previously complete any required remedial courses. Comparison of the performance of summer school students, which includes a significant percentage of transfers from four-year institutions, with that of traditional students, suggested that the course could be improved. Subsequently, changes were made including (1) class size reduction; (2) routinely including activity-based learning; (3) moving the classroom location to the Geology lab. Analysis of student grades and course retention indicates the following: (a) reduction of class size alone had negligible effect on grade performance and retention rate; (b) interactive teaching techniques led to raised student performance; (c) changing the class location caused an additional rise in performance. Following course modifications, there was an average improvement of one-half letter grade that has been consistently maintained for over four years. Furthermore, student grades and retention are positively correlated (r² = 0.73). Retention rates are now generally over 90%, with 100% retention some semesters. The course has become quite popular with students and end-of-semester student evaluations indicate a high level of student satisfaction.