[Bongle]

I don't think divisions would ever work. I don't think a team's performance one year necessarily implies how good or bad their performance will be the next year*. Especially in a high school competition where losing a team's only programmer, a leader, a welder, a mentor or a sponsor can happen in a snap, I don't think long-term organizing like divisions would be effective.

*I don't have time to do this right now, but a scatterplot graphing a team's percentile placing one year with their performance the next would quickly prove/disprove this hypothesis. If the plot is very tightly grouped around a line, then I'm wrong. If it is very spread out, then I am correct.