This document discusses strategies for effective learning. It recommends embracing difficult challenges which force deeper encoding of information into memory. Testing is presented as a way to check knowledge and identify gaps. The document also notes that learning builds on prior knowledge, so the more that is learned the more connections are formed to facilitate further learning. Repeated practice and effortful recall are described as ways to integrate new information into existing mental models. The overall message is that easier learning is not as effective as embracing difficulties which require more effort.