Having a group of political activists shut up for a day does nothing. They can't win anyone over to their side if they can't speak. Let these fools flatter themselves into thinking that they're "striking a blow for GBLT equality," and enjoy the silence. Sueing organizations over prostests like this is extremely foolish and has the potential to look aggressively reactionary.
Really? How long do you think the activists at the school district level worked to get this event into the school? How long do you think the activists at the county level worked to put this event into the districts? How long do you think the statewide activists worked on the counties? And how long did the national activists work on the states? All to get a bunch of yappy kids to zip their lips for an entire day so they can think about nothing but what it's like to be gay.
The point is, the kids aren't the activists. They're the targets of the activists. And the activists have hit their target square in the bullseye.