I gave my M&C class a test on Thursday. I really tried to make it easy, so more of them could pass. And I did the unthinkable--I gave them a review sheet a few days before with almost identical questions on it. If my AP knew, he would not be happy. I'm smarter than he is, though. I call the sheet practice, not review and I hide the real questions in with lots of other ones.
Some of the kids are good. They see through my tricks and manage to do quite well. Other kids have been beamed up to space somewhere and have been sent back to earth without some of their gray matter. For example, I gave them a question on combinations. I gave this one on the practice sheet nC2 = nC4 and the same problem with the 2 and 4 changed on the real test and at least 25% of the class got it wrong. I probably went over it 10 times before the exam and told them to beware. The also could not put these into their calculator and get the correct answer, even though I made sure to tell them they would have to do this on the exam. I did 1000!/999! on the board and on the test asked them 2000!/1999! and they couldn't do it. I know some of the stuff is hard, I try to teach the hard stuff, but put enough easy stuff on my exams so that everyone can pass. If only they would put the effort into studying that they put into goofing off, miracles could occur.