“People tend to try to learn in blocks,” Bjork said. “Mastering one thing before moving on to the next.”
Instead of doing that Bjork recommends interleaving. The strategy suggest that instead of spending an hour working on your tennis serve, you mix in a range of skills like backhands, volleys, overhead smashes, and footwork.
“This creates a sense of difficulty,” Bjork said. “And people tend not to notice the immediate effects of learning.”
Instead of making an appreciable leap forward with your serving ability after a session of focused practice, interleaving forces you to make nearly imperceptible steps forward with many skills. But over time, the sum of these small steps is much greater than the sum of the leaps you would have taken if you’d spent the same amount of time mastering each skill in its turn. –Everything You Thought You Knew About Learning Is Wrong | GeekDad | Wired.com.