Data-rich Case Studies Improve Students' Abilities to Interpret Graphs in a Large Non-majors Course

The authors of this TIEE Research Paper evaluated the use of data-intensive case studies and small group discussion on students' quantitative abilities in a large environmental science lecture course. Students were asked to interpret graphs in pre- and post-course assessments. Most students (>80%) thought they did well on the initial assessment, although faculty evaluators scored about half as below minimally acceptable. There was no significant overall relationship between how students thought they performed and how their responses were scored. Student confidence in dealing with quantitative information increased from the start to the end of the course. Their rated ability did not increase significantly overall, although those students who scored poorly in the pre-course assessment scored significantly higher in the post-course assessment. In general, male students felt more confident than female students about their responses to quantitative information although their rated scores were similar. No background data could account for variation in initial performance or change in performance. Improvements in lower scoring students are encouraging as are increases in student perceptions of ability. However, the large number of poorly performing students in both the pre- and post-course assessments, and the disconnect between how students thought they performed and how they were scored, means that actual performance may not increase with increasing perceptions of ability. Students may need more opportunities for feedback to confront the disparity between their perceptions and the reality of their lack of success in interpreting quantitative information.