“My students carefully read over their notes and highlighted the important parts, and now they feel very confident about the material.”

What’s wrong with this statement? It’s that you’re basing the effectiveness of a learning strategy on the students’ impressions, instead of on actual learning. We need to remember that when learning feels easy and effortless, this could actually be a red flag.

Robert Bjork first coined the phrase “desirable difficulties” to describe the idea that a certain amount of effort is important - perhaps even essential - to successful learning. This means that when using an effective learning strategy, students may actually appear to perform lower during learning than if they were using a less effective strategy.

Here are two situations that demonstrate this apparent contradiction:

Quizzing versus re-reading

According to surveys of student behaviour, they seem to favour re-reading their textbooks and notes over quizzing themselves. Cognitive psychologists have found quite convincing benefits of quizzing to learning, so why do students still prefer to re-read? One reason could be that repeated re-reading creates a false sense of fluency - reading the same information over and over feels easier and easier, which feels like learning. Retrieval practice, on the other hand, can feel bad - after all, who likes sitting in front of a blank sheet of paper and facing the holes in one’s knowledge? But persevering through that discomfort and forcing students to pull out information from memory is worth it if long-term learning is the goal.

Interleaving versus blocking

Another strategy that feels deceptively good is spending a long time consecutively practising the same topic (“blocking” or “massing” study). This applies most readily to maths classes. Let’s say you just taught your students how to calculate square roots: should they now spend a while practising square roots? The intuitive answer seems to be yes - they will do 100 of them and start feeling (and seeming) rather proficient. Despite appearances, though, if you later ask these students to calculate a square root cold - not after they’ve just done 100 of them - they may flounder. A more effective learning technique would be to have students practise square roots, while also practising all sorts of other related skills - perhaps squares and cubes. If students did this, they would not perform as well during learning as they would while calculating endless square roots in a row. But they would gain the ability to distinguish between different types of problem and pull out the right rule from memory at a later time.

What does this mean for teachers?

Try to give students learning tasks that challenge them, rather than those that make students feel good. If you are giving frequent formative quizzes, that’s great. But if students are scoring 100 per cent on them right away, you may need to increase the difficulty and intermix questions from different topics in order to increase long-term learning.

Dr Yana Weinstein (@doctorwhy) is an assistant professor at the University of Massachusetts Lowell. You can read more articles like this on the Learning Scientists blog. Follow the Learning Scientists on Twitter at @AceThatTest.

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