Hi Pam. You'll probably want to have a mix of mentors with skills in the areas of using AutoCAD, mechanical engineering, electronics engineering, software engineering, and machinist/welder. Some people possess one or more skills. That would provide a good skillset needed for designing and building the robot (specifically the chassis, drive train, controls/electronics and the programming).
Don't overlook anyone's ability to give to the team - some of our best ideas came from a businessman who thought he would be no help to us - we convinced him to stay and his ideas were simple to implement and quite effective. After we had spent days brainstorming - he spent one evening with us and we had a great design. He was quite surprised at how much he was able to help us.
Parents are very important because they always seem to know someone who knows someone who has access to this or that, - and they can help support the team with meals during the build period - we found that if we let the kids go home for dinner they never came back - maybe thats not true for most teams, but it happened to us so we started providing meals to keep the kids working.
Pattie