In taking my MBA courses and in helping 3 students through high school (1 yet to finish) and in helping my wife with her classes (teaching and taking) I've learned something about tests. There seem to be two types of tests: 1) tests to see how much the student knows and give a grade and 2) tests to show students what they should know and to give a grade.
These two sound very much a like, but they are very different. In the first case, the teacher/instructor/professor (TIP) may give a test with little or no preparation. A study guide may or may not be given.
The second case seems much harder. The TIP has to help students through the test. In one class I was in, the professor would give a take-home test in one class, the next class he would ask if there were questions. He would work similar problems or talk around the subject. If there weren't enough questions, he may even delay the due date so he could generate more questions.
In tests like the first case, there seems a tendency to cram for the test. You study everything in the world and then take the test quickly before you lose it. After the test, your brain drains off all the knowledge that you flooded it with before the test. The net increase in knowledge is minimal.
I like the second case much better. I think I learned better in classes that did this. Hats off to the TIPs who did this....