Nick is right - you'll never get it down to zero, and not only for the freshmen. We always lose some seniors to senior play (invariably the same weekend as Bayou), and others to changing family or work requirements. We have managed to reduce the attrition rate by communicating expectations early, not only to the students, but to their parents (we did two parent meetings in the past week). Additionally, we now hold "tryouts", which takes place three nights a week for two weeks (a bit longer last year), on Monday, Thursday, and Saturday (the same days as our early build season schedule). If people can't make those, they probably won't make build season. We test for both attitude and aptitude, and mostly select on attitude, filtering out whiners, distractors, and those who just don't really seem interested in trying new things. We use aptitude scoring as well as team member input and our needs to determine who will end up doing what.
Our first four years, we started build season at three nights a week and built to four, five, or (rarely) six as the season progressed. This was because we were meeting in a classroom, so our head coach really had to be there nearly every session. We did find that having a "programming night" each week (3-6) with maybe one build team member and two controls/wiring members as well as all or nearly all of the programmers really worked well. There were also occasional build-only sessions, and maybe one or two controls-only sessions. On the whole, however, we find that we really want to have at least a representative of each discipline at every meeting, to help keep each group up to date. This year, our robot build will be in an out-bulding (affectionately known as "the shed: the middle of the five small buildings
here"†) and we're planning to have cross-functional project teams, which should make "partial team" meetings even more feasible.
We have never required every member (or mentor) to attend every hour of every build session, but we definitely have a minimum number of expected hours per week to qualify/maintain status as junior varsity, varsity, and officer/team leader*. The big difference between JV and varsity is that JV doesn't get the field trip to to Bayou Regional on Thursday or Friday. We did bring our two top JV fund-raisers to CMP last year.
When thinking about burnout, also consider the coaches and mentors. For some of them, their regular two-week vacation from work may also cover burnout, for others, a bit more time may be in order.
Lettering - we require students to meet at least 3 of four requrements to letter:
Being a member
- of the varsity team at the end of build season (this usually means that you have become "essential" to the team as well as meeting the hourly goals)
- Fund-raising. The dollar value changes year to year. We also recognize major fund-raising efforts, whether or not they result in the expected dollar figure.
- Community Service Hours. We include CS hours arranged through the team fully, and outside CS hours (e.g. soup kitchens, church mission trips, Katrina rebuilds - yes, they're still going on) at 1:2.
- Being active (actively participating, not just a nominal member) on a committee/business function such as web design, media, history project, sponsor renewal, grants, spirit.
* - While we've never set explicit numbers, the same is true for "watch mentors". We want to have one mentor "on watch" in or near the pit throughout our active pit hours, but the eligible candidates are selected based mostly on their commitment level. The goal (met this year) is that the student pit captain can handle everything and the watch mentor is only there as backup should things turn truly sideways. Oh, wait - the pit captain had to leave for about three minutes Friday afternoon to handle a situation and left me "in charge". Nothing untoward came up in those few minutes.
† - be it ever so humble, there's no place like home, eh?