I was on a FIRST robotics team as well my senior year. I basically founded the team in high school as I was building robots for Science Fairs and not getting much recognition for it there. (Although I made some good prize money the first year.) The team was about 12 or so good friends and other people generally interested in robotics. We did fairly well for a rookie team we competed in Cleveland and Grand Rapids. A friend of mine who was terrible under pressure drove in the Cleveland competition, we finished mid pack out of 70 or so teams. I drove in Grand Rapids and we finished 7th out of 70 or so teams.
Good times.
I mentored my freshman year in college. The team was already headed downhill I could tell. Too many people joining to just hangout and get a free trip out of it. (My girlfriend at the time was one of them.) That was my last real experience with the team.
My brother-in-law an electrical engineer mentored every year since I started it. He told me how it kept going down hill.. eventually it died last year.
Its a good program. You can learn a lot if you take advantage of it. Do as much as you can and learn as much as you can. Welding, machining, CAD, wiring... its all in there soak as much of it up as you can.