When they asked me how I was doing it I explained that I'm there to learn understand the topic and I don't give a damn about the test. So I just let my curiosity lead the way, it causes me to ask questions in and out of class, email the professor about them, do my own research and experiments. Despite not letting the test be my guide, this prepared me for the test anyhow.
I'm glad they work for some people, but flashcards to me seem like they provide a shallow kind of understanding. I don't want to remember the equation, I want to be able to derive it in a pinch, and flash cards don't give me that.