Examining Exams

But it's bad advice, as it turns out. When the psychologists looked at these different strategies in the laboratory, they found some striking differences in real learning, all favoring more, rather than less testing. Everyone learned the Swahili words fairly quickly, no matter how they approached the material. But the differences showed up a week later, when the volunteers were tested for long-term retention. The learners who kept on testing, even after mastering a new word, had much better retention of the word list a week later, compared to those who had studied the words over and over without testing. And the differences were dramatic: Those in the "more study" group recalled only 10 to 60 percent of the words, while those in the "more testing" groups remembered from 63 to 95 percent.

Why would this be? Well, basically, the psychologists were studying and comparing the fundamental building blocks of memory—the original encoding of new information and its subsequent retrieval—to see which is the more powerful engine of long-lasting learning. And the results were unambiguous: It's the digging up of newly stored information, the way you would when answering questions on a test, that really sets it in concrete. Repeated attempts to enter new words into memory—no matter how many repetitions—produce nowhere near the same level of retention. The psychologists ran other experiments on more complex learning—remembering the meaning of prose passages, for example—and got the same results.

In an interesting twist, the psychologists asked the different groups of volunteers—all college students—to predict how well they would recall the Swahili vocabulary a week later. They found that they were equally confident in their learning whether they had spent more time testing or more time studying. In other words, students are unaware that self-testing is a much more effective use of their time than additional study, and indeed questionnaires show that few students ever use it as a tool for study.

There are certainly good arguments against too much testing, especially when it's done at the expense of problem solving and experiential learning. But the fact is, even the most creative students need a foundation in basic knowledge. Despite my whining, I like knowing my times tables today, and am much happier when I can order dinner in a foreign language rather than pointing and mumbling. So I guess I'm ready to give two cheers for a little testing tyranny.

Wray Herbert writes the "We're Only Human" blog at www.psychologicalscience.org/onlyhuman .

© 2008