Think about it this way:
If you went to prom you could possibly have a good time some friends, or you could end having a terrible time depending on how well organized the event is. If you go to nationals, however, you will most certainly have a good time with thousands of friends from all over the world, while participating in something you love!
I, and three others from my team last year, missed our senior prom for the
Brazil International Event (which I suppose is somewhat different). It was sad to have to miss the prom as you only get to do it (at least as a senior in your own school) once, but it was certainly well worth it for such an amazing experience, and nationals are the same way. While it may be hard for "outsiders" to understand your decision, you'll know that you made the right choice when you're standing there in Atlanta watching 6 amazing robots go at it for the big win.
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Mentor to Teams 555, 1929, and 2070!
Currently working in hardware design at Cisco.
Cornell University DARPA Urban Challenge -
http://www.cornellracing.com
Co-Captain Team 555 - 2003,2004,2005
Trust, Love, and Magic