[EricH]

Add my vote for the team category. Exact ratios aren't important, as long as a team builds it. (If it's a dysfunctional team, that's important for other reasons, like the "what went wrong/right" meetings, but the split percents are not. I hope that no team here is dysfunctional.)

As for the definition of building, I would just say: Entire process, from concept generation to final product, programming included.

Mostly: Do the students or the mentors do most of the building as a group?