All religion or just one :-)
Carefully crafted comparative religion classes would be fine in, say, high school. Encoraging attendance of a particular type of church or temple or mosque or "reading room" should be prohibited. And children who don't believe in any other type of theism should not be stigmatized or indoctrinated either. The simplest way to avoid that is to keep religion out of schools except in a carefully crafted comparative context.
And I'll go farther than that: Schools should not encorage attendance or association with any particular non-school association. They shouldn't encorage participation in the Boy Scouts as opposed to the Boys Clubs. They shouldn't encorage participation in Habitat for Humanity as opposed to the Audubon Society. They shouldn't encorage participation in 4H as opposed to a Junior Chamber of Commerce. Students should be free to participate in service groups that best match their interests.
Schools should encorage children to become members of groups that improve communities and society. They should not be exclusive about that encoragement. That goes triple for religion, IMO, because there's so much baggage with it.
Cheers,
Scott.
