Exploring Topics in Depth with very little time

After analyzing my grade 11 student test results and comparing them with last years, I have begun to think about how I could help them understand the material a little better. I began to think that I was evaluating material differently than last year. Last year, communication was on all tests and most people did very well in it. This drove up marks, I believe, quite a bit. This year, I am not doing this and although I am not convinced that this alone accounts for a drop in averages, it has made me rethink how I explore the more difficult concepts with the students. Let's take motion graphs and their analysis, as an example. It is one area that I think is not easily grasped by students. They don't have enough examples, or enough feedback when they try to figure things out. This makes the understanding of the material very difficult. Also, from a teacher's perspective, giving enough feedback for students to be succesful may be too timely. So, what is to be done? Well, I thought of the following strategy. I have always been an advocate of having students come up with the work required for future students, the problems is that they often lack the experience in both the subject and in pedagogy as a whole to provide a piece that is truly worthwhile. What I suggest, and this can work for any topic, is to give each student an example of four different motion graphs and they are to come up with four different multiple choice answers for each graph. For example, say the velocity-time graph is a simple line going from positive to negative, sloping negatively. The four answers could be a) an object moving at a constant rate negatively b) an object moving at a constant rate positively c) an object that is decelerating to a stop d) an object that is accelerating in the negative direction, which means the object stops instantly and then goes in the opposite direction. The students will have to duplicate the graph and come up with the four answers, one of which has to be right. I would then ask for their files and mark them. This would give me a database of questions and multiple choice answers. I could alter any that were wrong and then compose a quiz online that would give the students feedback. I could vary up the graphs to have a truly awesome amount of questions, with very little work for me and the students would produce the device that would eventually be educating them.