LiveScience recently posted the results of a study looking at the connection between test-taking and memory. Their title is a bit misleading, making the claim that test-taking leads to an improved memory. What the study really reveals is that it's not so much the test as it is the opportunity to review. And sleep. "Based on the results, the researchers, led by Jason Chan of Washington State University in St. Louis, recommend that 'educators might consider increasing the frequency of testing to enhance long-term retention for both the tested and the related, non-tested material.'"
This is not really news. There's lots of research out there to support the importance of having practice with information in order to achieve mastery. I used to talk with students frequently about the importance of sleep...something often lacking in the lives of teenagers. It's not just the rest your body needs, it's the opportunity for your brain to process the things encountered during the day and reinforce new neural connections it has made. If you don't sleep, there is even less of a chance of retention.