Practicing different skills in quick succession can lead to massive gains in learning

Jeremy Dean
PsyBlog
Fri, 04 Sep 2015 00:00 UTC

Despite multiple studies showing the benefits, many people don't know this learning trick.

Mixing up your learning can lead to massive gains, a new study of academic performance reveals.

For years now 'interleaving' has been a secret largely confined to researchers.

Interleaving means practising or learning different skills in quick succession.

When interleaving, tennis players might practice forehands, backhands and volleys altogether.

Interleaving for musicians could mean practising scales, arpeggios and chords all in the same session.

It's quite a different method to how people normally learn.

Tennis players typically focus on forehands for a session and musicians on scales for a session.

The benefits have been shown in studies of motor skills:

"...college baseball players practiced hitting three types of pitches (e.g. curve ball) that were either blocked by type or systematically interleaved.

During a subsequent test in which the three types of pitches were interleaved (as in an actual game), hitting performance was greater if practice had been interleaved rather than blocked.

A similar benefit was observed in a study of basketball shooting..." (Taylor & Rohrer, 2010)

A new study, though, shows the dramatic benefits of interleaving on children's performance at math.

For the research some kids were taught math the usual way.

They learned one mathematical technique in a lesson and then practised it.

A second group, however, were given assignments which included questions requiring different techniques.

The results were impressive.

On a test one day later, the students who'd been using the interleaving method did 25% better.

But, when tested a month later, the interleaving method did 76% better.

That's quite an increase given that both groups had been learning for the same amount of time.

The only difference was that some learned block by block and others had their learning mixed up.

One of the potential drawbacks of the technique is that it can feel harder at first.

Instead of concentrating on one skill at a time, you have to work on two or more.

But interleaving probably works because it forces the mind to work harder.

Instead of relying on learning a system and sticking with it, the mind has to keep searching and reaching for solutions.

The research was published in the Journal of Educational Psychology (Rohrer et al., 2015).

Comment: From Obsessive practice isn't the key to success - Here's why:

While practicing is vital to learning and memory, studies have shown that practice is far more effective when it's broken into separate periods of training that are spaced out. The rapid gains produced by massed practice are often evident, but the rapid forgetting that follows is not. Practice that's spaced out, interleaved with other learning, and varied produces better mastery, longer retention, and more versatility. But these benefits come at a price: when practice is spaced, interleaved, and varied, it requires more effort. What you don't sense in the moment is that this added effort is making the learning stronger.