You'd be hard pressed, looking at me now, to guess that I was once a reasonably good tennis player and even gave lessons on occasion (in tennis and racquetball). My teaching technique was extremely simple. There were two points to remember: (1) racquet back and (2) follow through. Then over and over again with repetition the key way to learn, since the issue is not intellectual; it is all implementation. Everyone can understand racquet back - get ready for the ball before it arrives so you can swing when the ball is near. It is astonishing, however, especially for those who haven't played sports their whole lives to watch how poorly the novice implements this rudimentary idea. The novice takes the racquet back when the right thing to be doing is swinging forward. So the novice is constantly late with the swing and off balance. Racquet back as a metaphor for good preparation is something everyone should appreciate.
Follow through is conceptually harder. Most people want to hit (at) the ball. It turns out that if that is your mindset, then you actually decelerate your racquet head at impact. So instead, they teach you to hit through the ball in a wide swing that ends far from the point of impact. The mindset should be to think where your hand and racquet head end up at the conclusion of the swing so you have good momentum at the time of impact.
I want to take this sports notion of follow through and apply it to the other notion of follow through that we use (getting the work done), in particular applying it to the work students do on course projects. My argument is that students do the analog of hitting at the ball when they do their course work. One of the main reasons, I believe, that we should encourage the re-use of student work, is that students change their thinking about what they are doing. If a project is for the instructor to grade and that's it, then the activitity has value to the student for the grade and for what the student learns while doing. The latter may be what the instructor really wants to achieve but the student may very well not perceive that at the time the work is being done. If the project is done only for the grade, that is very artificial as a source of motivation and it hard to imagine that good work will be produced as a consequence.
Now suppose instead that the assignments are done so that other students in the class will "consume them" in some fashion. (I've discussed how the content surveys created by some students can be administered to other students and then all can partake in class discussion on that basis.) This can be generalized to other types of work and potentially other audiences than classmates within the current cohort. But let's stick to that type of re-use for this discussion. Now the student work has value past the learning by the creator and matters to the others in the class. So the student creator is put into a situation where others are dependent on the creator's effort and that social need changes the focus and exerts some pressure on the creator to deliver something that is useful to the others. The point to emphasize here is that the re-use by others should have a salient effect on the quality of what the students create. To stretch the metaphor, the impact should be better because of the follow through.
As you know I'm an economist and we economists try to rip to shreds the type of argument in the previous paragraph on the following point. If the re-use doesn't have value in itself, if it is used purely as a motivational device for the creators, but really after the creation the instructor steps in with her own view of the right way to motivate the discussion and doesn't expect the other students to react seriously to the creators' content because, after all, the student creators are not experts and don't we have an obligation in instruction to expose the students to expert opinion, then doesn't the whole thing fall apart? Economists call this the issue of credible commitment. I certainly agree that incredible commitments don't work. Is re-use of student work something an instructor can credibly commit to and if so, how is that commitment obtained? It is a critical question to answer if we are to have follow through.
In my own teaching, I've convinced myself this is credible for the following reasons: (1) students actually benefit from initially penetrating a subject based on the work of other students because the entry requirements are less and they will find the work more accessible, (2) students should be exposed to the works of other students as a way to benchmark their own work and hence they will be more comfortable and at ease, (3) the instructor's role can be seen as adding layers of expertise on top of the introductory layers that the students have created and thereby give the class the sense that learning is about getting additional perspective and nuance in view, and (4) during the time when the groups are making the re-usable work the instructor has a legitimate reasons to coach the groups into producing the best possible work so the mechanism is a way to implement learner centric approaches, which all good teachers are after. In other words, the credibility of the commitment depends critcally on the eye of the teacher on how the work fits in with the goals she is trying to achieve in class. It is not just the students who need to follow through.