The initial concept was more about generating a learning resource; a solutions manual to accompany their textblooks (sic). Now I find myself emphasizing the nature of learning that takes place when they make their "Constructive Modifications" as the real purpose of this assignment.
David Warlick has been emphasizing that the jobs for which the school system should be preparing our students do not yet exist. More than that, no one knows what they will be. One thing these "new jobs" will have in common is that they will be in the nature of "knowledge work." It wont be as much about what you know as it will be about what you do with that knowledge.
In December we had a career day at our school. We had over 50 professionals in the building describing the pursuit of different careers. We had RCMP officers, doctors, graphic artists, business people, people representing all sorts of opportunities. There was one common thread in every presentation. What kids learn in school today is secondary to them learning how to learn. The attitude of business is: "We'll train them with what they need to know. You just teach them how to learn." Even the RCMP officer emphasized several times that an important part of the application would be evidence of life long learning. He said: "We don't really care what you're learning as long as you can demonstrate that you're continuing to learn."
As I said in the discussion over at Clarence's blog; this ties in with the idea of Assessment As Learning. The kids think the "Significant Contribution" is the hard work. This week I've explained to them that the purpose of the "Significant Contribution" is there for a variety of reasons, but mainly to enable them to make their "Constructive Modifications" which is the real hard work.
A "Constructive Modification" must be an edit of someone else's work. In order to make a "Constructive Modification" that moves the project forward in a constructive way they have to scan through much of their classmates work. Think about it critically. Assess it for accuracy, clarity and presentation; and then decide what they will do to modify it so that it is better than it was before. The actual content generated this way may be small, in comparison to a "Significant Contribution," but it requires deep metacognition and critical analysis -- an awful lot of thinking and (hopefully) an awful lot of learning.