The constitution says freedom "of" religion. Not freedom "from" religion. Be an Atheist if you want, but don't throw a hissy fit when people feel their rights to religious freedom are being impeded upon.
the title of this thread reminded me of the past christmas. My dad decided to dress as Santa. Everything was good. All the family was joking around, everything ok. He, dressed as Santa, took a bottle of champagne from the table and my little sister saw that. She left to her room and started to cry non-stop. Nobody knew what was really happening. Until she broke silence and said "We killed Christmas, didn't you noticed Santa took a bottle of alcohol! Now he's going to crash and it's all our fault!" Hahah, so funny, yet so innocent of her!
It also says Seperation of Church and State. Public schools are state run. Therefore all that religious stuff should be kept out. If you want you're child to learn about the origins of Christmas you either teach them yourself or you send them to a private school.