Volume 9, Number 3: November 27, 2002
by Christy Carello
University of Wisconsin-Eau Claire
Introduction Experimental Design For the first assignment one group was required to present the papers using overheads and the other group was required to use PowerPoint. For the second presentation the format was switched for the two groups. This alteration in the format for presentation naturally controlled for expected improvement in presentation performance. Two undergraduate teaching assistants and myself scored the presentations and the students were awarded a grade that was an average of the three scores. After each set of presentations was completed an identical exam was given to both sections on the content of the papers. I used correlation and regression analysis, and the Student T-test to evaluate presentation scores, exam scores and overall class grade. Results There was no difference in
student presentation grades between overhead and PowerPoint presentations
(t = 0.212; p = o.417; Figure 1). However students did show significant
improvement in their presentation grade between the first and second
presentation (t = 3.10; p = 0.002; Figure 1).
Students showed no significant difference in their performance on exams based on papers presented using overheads and PowerPoint (t = 0.092; p = 0.464; Figure 2). In addition, there was no significant difference in overall exam performance between the first exam and the second exam on the material presented by the students, regardless of presentation medium (t = 0.046; p = 0.482; Figure 2).
In general, the only strong correlation relationship was between performance on presentation exams and overall class grade (0.57). Students who scored well on the exams also performed well in the class (Figure 3). Figure 3. There is a positive relationship between exam scores and final class grade.
The quality of PowerPoint presentations was equal to the quality of overhead presentations when judged by both undergraduate student teaching assistants and faculty. Students' scores on presentations did not differ based on presentation styles. However, students did show significant improvement in giving a second presentation. Therefore, practicing the presentation is more important than the format for the visual aids. Based on exam performance the student audience learned equally well under both media conditions. In fact the only variable correlated with exam performance was overall class grade. This was surprising because both exams combined were worth less than 5% of the overall class grade. Even the presentations, worth a total of 19% of the class grade, did not correlate with overall grade. Overall, good students performed well in all aspects of the class. Whereas, the average grade on the oral presentations was higher than the average grade for the course, suggesting that this was a relatively easy assignment compared to the other assignments and exams in the course. Even though the PowerPoint presentations did not improve learning by the student audience and student presentation scores were equal using both PowerPoint and overheads, I feel that learning to develop PowerPoint presentations is a valuable skill. Students can now use PowerPoint for future presentations and in the job market. In addition, I found students to be more creative in developing their project, and they performed additional research on their topics on the Internet in order to find relevant images to use in their presentations. My students reported to me that they enjoyed preparing these presentations more than the overhead presentations. I firmly believe that students embrace learning more when they enjoy the process. In the future, I will encourage students to use PowerPoint for their presentations. References Fifield. S., and R. Peifer. 1994. "Enhancing Lecture Presentations in Introductory Biology with Computer-based Multimedia." Journal of College Science Teaching 23(4): 235-239. Mantei, E. J. 2000. "Using
Internet Class Notes and PowerPoint in the Physical Geology Lecture."
Journal of College Science Teaching, March/April: 2-6. |