OCCRA stands for the Oakland County Competitive Robotics Association, started I believe it is now.. 4 (?) years back with the purpose of continuing the FIRST spirit through the fall. Although FIRST teams do attend off-season competitions, OCCRA is somewhat different than those competitions, in a few aspects.
1. The OCCRA games are different from the FIRST games. Both may share a lot of similarities, however. For example, last year in OCCRA, we had goals that very much resembled the goals in this year's FIRST game. We had a 2v2 format for a 2 minute game, with human players as well.
2. Like FIRST, teams compete in multiple competitions (those are held at local high schools). But unlike FIRST, all teams have the opportunity to participate in the county championships.
3. In OCCRA, the robots are completely student-built. We're limited to hand tools. No machine-shopping for the most part
We have.. ohh.. about the same time constraints as FIRST.
4. A team needs not be in FIRST to participate in OCCRA. In fact, I believe that a few teams have joined FIRST because they've so enjoyed their experience in OCCRA.
5. After the county championships, an all-women's tournament is held. The game is modified, and the girls on the teams are given approximately one week to make changes to the robot that would best fit the modifications. An example of a change is a decrease in ball size.
6. Competitions last one school night, with the exception of the county championships and the all-women's tournament, which last a whole Saturday.
That's all I can come up with for now.. Maybe more to come later. All in all, OCCRA is pretty similar to FIRST, even the robots have about the same constraints (volume and weight, materials used). And like FIRST, it's loads of fun!