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Should teachers give cumulative final exams? According to laboratory research, doing so should enhance learning. But lab results do not always translate to the real world.
A new study by Natalie Lawrence (2013) took it into a real introductory psychology classroom. (Update: Check out two more studies showing that final exams enhance long-term learning here and here.)
The author taught two sections of intro psych with a total of 105 students. Each section took three midterms and a final exam. The only difference was the midterms.
- In the non-cumulative condition, the midterms included new material, but they did not ask about information that had been introduced prior to the last exam.
- In the cumulative condition, 80% of the midterm questions covered new material and 20% covered material from prior tests.
The two classes then took the same cumulative final exam, as well as a follow-up test, using all new questions, two months later.
Because there was no prior test, both conditions took the same first midterm. They did equally well, suggesting there were no a priori differences between the groups. Students were split into high and low ability based on this test.
The results
Students who took cumulative midterms did better on the final exam. They got 80% correct, compared to 77% for students who did not take cumulative midterms.
On the followup test two months later, only 64% of the students responded, and low scorers were less likely to respond, so there may be subject selection effects. But the result was that low scorers benefited from cumulative exams, whereas high scorers actually did slightly better if they had been in a non-cumulative section (but apparently they were significantly better).
A survey of the students showed they weren't happy about taking cumulative exams.
Why are cumulative exams beneficial? Probably multiple reasons. Szpunar, McDermott, and Roediger (2007) showed that students learn more if they expect a cumulative final even if they don't take one, because they study differently. And taking the test is probably even better; lots of research on the spacing effect shows that learning something and then restudying/taking a test on that something can have a huge impact on learning.
The bottom line
Cumulative tests are what cognitive psychologists call a desirable difficulty: They enhance learning but students do not like them. Are they worthwhile? The answer appears to be yes, especially for students who are struggling.
References
Lawrence, N. K. (2013). Cumulative Exams in the Introductory Psychology Course. Teaching of Psychology, 40, 15-19.
Szpunar, K. K., McDermott, K. B., & Roediger III, H. L. (2007). Expectation of a final cumulative test enhances long-term retention. Memory & Cognition, 35, 1007–1013.
