This reminds me of the many Americans who believe that "separation of church and state" means that it is forbidden to discuss religion, or things religious, in public schools. This is complete nonsense. It is forbidden to compel students to subscribe to a particular religion (evangelizing), but not to discuss or inform. It's also not "against the constitution" for students to gather on school grounds for a religious purpose, as long as it does not violate any laws and is strictly voluntary. :0)