Google's natural results are determined by result relevancy. It means that, when people search Google for "FIRST" or "FIRST Place," many of those people then click on links to
www.usfirst.org. Google sees this and, as a result, ranks those results higher than others that see less traffic.
A great majority of search terms on Yahoo! for the month of November that included the word FIRST are not appropriate for these forums and thus, another reason why you'll see it ranked relatively high for such a generic term.
"FIRST Robotics" received 1200 searches on Yahoo! in November. I would be curious to see what percentage of referrals from Yahoo! that is.
Also, I'm curious who FIRST uses for their paid search advertising and how well it performs.