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The Trouble With Homework: Using Science to Learn Better

The quantity of students’ homework is a lot less important than its quality. And evidence suggests that as of now, homework isn’t making the grade.

Here are some simple and easy to carry out ideas (backed by science) that will help you improve your ability to absorb, retain, and apply knowledge:

“Spaced repetition” is one example of the kind of evidence-based techniques that researchers have found have a positive impact on learning. Here’s how it works: instead of concentrating the study of information in single blocks, as many homework assignments currently do — reading about, say, the Civil War one evening and Reconstruction the next — learners encounter the same material in briefer sessions spread over a longer period of time. With this approach, students are re-exposed to information about the Civil War and Reconstruction throughout the semester.

It sounds unassuming, but spaced repetition produces impressive results. Eighth-grade history students who relied on a spaced approach to learning had nearly double the retention rate of students who studied the same material in a consolidated unit, reported researchers from the University of California-San Diego in 2007. The reason the method works so well goes back to the brain: when we first acquire memories, they are volatile, subject to change or likely to disappear. Exposing ourselves to information repeatedly over time fixes it more permanently in our minds, by strengthening the representation of the information that is embedded in our neural networks.


A second learning technique, known as “retrieval practice,” employs a familiar tool — the test — in a new way: not to assess what students know, but to reinforce it. We often conceive of memory as something like a storage tank and a test as a kind of dipstick that measures how much information we’ve put in there. But that’s not actually how the brain works. Every time we pull up a memory, we make it stronger and more lasting, so that testing doesn’t just measure, it changes learning. Simply reading over material to be learned, or even taking notes and making outlines, as many homework assignments require, doesn’t have this effect.

Earlier this year, researchers from Purdue reported that students who used retrieval practice to learn science retained about 50 percent more of the material than students who studied in traditional ways. “It’s simply an effective way to focus less on the input of knowledge (passively reading over textbooks and notes) and more on its output (calling up that same information from one’s own brain).”

one last tip:

Another common misconception about how we learn holds that if information feels easy to absorb, we’ve learned it well. In fact, the opposite is true. When we work hard to understand information, we recall it better; the extra effort signals the brain that this knowledge is worth keeping. This phenomenon, known as cognitive disfluency, promotes learning so effectively that psychologists have devised all manner of “desirable difficulties” to introduce into the learning process: for example, sprinkling a passage with punctuation mistakes, deliberately leaving out letters, shrinking font size until it’s tiny or wiggling a document while it’s being copied so that words come out blurry.

Source: Annie Murry's op-ed in the NYT

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