Wes Fryer liveblogged and UStreamed a school board meeting last week and wondered a little about the legal implications thereof.
Short answer: Yes, you probably can video record or liveblog school board meetings unless someone tells you not to because it is going to disrupt the meeting or a local rule exists prohibiting recording.
Long answer: Okay, I am going to cheat here and let the Citizen's Media Law Project do it for me. Also check out their state specific rules.
Let me just add to the long answer that FERPA and other privacy issues could potentially come into play in schools more frequently than other arenas. School boards should be going into closed sessions for these issues anyway, but if you notice them making a mistake and talking about private issues in public, you may want to help them out and keep the student's or teacher's information off the airwaves, or in this case the "series of tubes." Otherwise, I think the long answer works just as well for school board meetings as it does for Congressional Hearings.
Practically, the liveblogging I don't think will ever be a problem. Public officals are becoming comfortable enough with folks typing away on laptops that I don't think that would ever be a disruption. The video recording could be a disruption, but the less of an issue you make it, the better. Wes' plan to record with a camera phone I think was good - it doesn't really get in the way of anything. Now, if you brought in three extension cords, lighting, an overhead mike, etc... then it is likely going to be a disruption. Also, practically, it is probably not worth annoying board members and being as polite as possible. Asking ahead of time is probably a good idea, but have a fallback plan in case they say no to the initial request.
One of the commenters in Wes' liveblog noted that he would like to see a trend emerge of webcasting school board meetings and I also think that would be a good idea. For instance, Wes had a viewer from New Zealand watching that central Oklahoma school board meeting. That's just cool - and probably a good thing for our democracy.