The New York Times:
The math students at Liberty Middle School were not happy. The seventh graders’ homework was harder and more time-consuming at first, and many of the problems seemed stale. They were old, from weeks or months ago — proportions, again? — and solving them interrupted the flow of the students’ current work.
“The result is that you feel you’ve learned the material really well; people prefer blocked practice, when you ask them,” said Robert A. Bjork, a psychologist at the University of California, Los Angeles. “But they do much better on later tests when they practiced interleaved, or mixed, sets of problems or skills. It’s completely counterintuitive.”
The researchers started small: eight seventh-grade pre-algebra classes, 140 students in all. “We didn’t introduce anything new, or ask teachers to do any additional work,” said the lead investigator, Doug Rohrer, a psychologist at the University of South Florida and a former math teacher himself; his co-authors were Robert F. Dedrick and Kaleena Burgess. “We simply rearranged the material they already use.”
“But I’m much more concerned with how these lab-based techniques interact with everything else in the classroom: the different dynamics, different kids, different teaching styles. For example, some percentage of teachers are going to say, ‘This doesn’t fit with how I teach math.’ Period. A lot of other people are simply not going to grasp what’s required to make it work. The question is: Is it adaptable?”
Most psychologists who study learning think so. “Remember, learning is slower when you begin interleaving,” said John Dunlosky, a psychologist at Kent State University. “If you have both groups learn the material to the same level — that is, if you give the people doing interleaving a little extra time at the beginning — then the benefits of mixed practice will be even larger, I expect.”
Read the whole story: The New York Times