Good topic...
Well since I went to a public high school that was DILAPIDATED (sp.?) and to' down
I would probably concentrate on improving the conditions of the schools in the lower-income areas. It is funny how when you go across town to the more upscale neighborhoods, there are state-of-the-art schools with enough supplies for every student. I remember when I was in school we only had enough books to keep in the classroom (we rarely got books to take home...the only classes I can remember taking books home for were my math and science classes) and even then we had to share.
I believe funding for public schools was based on the property taxes for the surrounding area, so naturally the upper-class areas had better schools.
So, based on my experience, if I were on the school board I would try to ensure that funding for public school is distributed EVENLY among ALL schools and abolish the property tax funding.
BTW I like Chi_ZETA's idea...at my university we are required to take a diversity class and a class with a mulitcultural theme to graduate. I think it should start MUCH earlier than the university level, though. Like in elementary school.