It should be based on what you want to be able to do at the end of the course.. So, give a test at the beginning - asking the student to do something, which she is obviously not able to do. Then, provide the answer - even though it doesn't make sense - and say where in the course the user will learn the critical concepts. Where is the desirable difficulty? Where is the spaced repetition? These should be familiar concepts to Coursera folks. What kinds of daily drills can you use to warm up and stay sharp - when you are taking a certain course?