Interleaving is a powerful strategy that boosts learning by mixing up content students need to learn. Based on a wealth of cognitive science research, the challenge and "desirable difficulty" of interleaving can double exam performance compared to teaching content in "blocks" of the same concepts. But what's the secret to effective and fruitful interleaving? Mix similar topics. Read more about why and stay tuned for next week, when we'll share quick how to's.