It's a strategy of mixing up the type of problems you solve when you're testing yourself.
That way, the testing conditions are more similar to real life, where you first have to figure out what kind of problem you have on your hands and then solve it.
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... you need two kinds of prior knowledge:
When learning is difficult, you're doing your best learning, in the same way that lifting a weight at the limit of your capacity makes you stronger.
When you keep trying to remember a piece of information, you interrupt the forgetting process and help cement the memory of that information into your brain.
You're experiencing fluency when you're reading something and it feels easy.
For example: you're at the airport and you're trying to remember which gate your flight is. You look at the terminal monitors — it's B44. You think to yourself that's easy to remember. Then you walk away, idly check your phone, and instantly forget where you're going.
When you're weaving in new threads into your pre-existing web of knowledge, you're elaborating.
The more you can explain the way your new learning relates to prior knowledge the more connections you create that will help you remember it later.
When people have the opportunity to reflect, they experience a boost in self-efficacy and self-confidence.
As a result, they put more effort into what they're doing and what they learn.
Retrieval is when you try to recall what you've learned. There are many ways to do this, some better than others.
Why it works: It strengthens your memory and interrupts forgetting. The act of retrieving information helps facilitate long-term recall.
How to apply it: Summarize the material in your own words. Don't copy and paste it; you won't get the learning benefits from it. Use your own memory, even if it feels hard.
When you try to give an answer before it's given to you, you're generating.
In an academic setting, you could work finding your own answers before class starts. In a professional setting, you could supply your own ideas when you're stuck before talking with your boss.
Learning is hard and takes effort on a personal level. It requires attention and physical energy.