Too bad we let the cults of environmentalism and sex idolatry persist though.Then that community is establishing THE religion, even if it allow other religions to practice outside of that venue. Government giving one religion privilages another religion isn't allowed IS establishing a religion.
I don't get why evangelicals push this state power so hard. By all means, spread your word. That's the great commission. It IS a major part of Christianity. It's a free country. Just try not to violate other people's rights and you're good to go. But you don't get to use the power of the state to do it. But, everyone should get equal treatment. So allow all religious artifacts in schools, or none. No special treatment.