One important thing to remember is that next year, FTC will probably use a different robot system, not Vex
. Vex plans to hold competitions, similar to
Bridge Battle, but they will be independent of FIRST. Some teams will choose the new FTC robot system and go with FIRST (system not yet announced), others will choose to go with Vex, and some well-endowed teams may buy both sets of equipment and do both competitions. Before you invest in any equipment, you'll need to decide on which direction you plan to take. If you decide to go the Vex route, here are some resources for beginners:
http://www.chiefdelphi.com/media/papers/2019
http://www.chiefdelphi.com/media/papers/2029
You don't necessarily need to recruit a lot of team members to have a successful team. Ten is the limit for a team, and I've seen good FTC teams with as few as 2 members. If you only have one robot kit, it's hard to have more than 3-4 students working on the robot at once. If you have many more students than that, they'll probably just be sitting around unless they're channelled into doing something else like working on T-shirts, website, CAD, publicity/fundraising, or journal writing. You can get more members involved if you have more kits, but you have to have the funds for those extra kits.
Best wishes for a successful team!