He does not have to recite pledge, already decided in West Virginia Board of Education v. Barnette in 1943. The "must stand" bit is pretty much felt to be the same but the court did not speak to it. ACLU will eat the school district and rightly so I think. Those soldiers we speak of fought for freedom of speach among other things. Freedom of speach also includes freedom from speaking (or standing). You can punish him if he doesn't sit quietly, but just sitting while others stand and recite IS speech (just speech some don't like).