" Forcing ALL children to repeat the Lord's Prayer, no matter what their religion, is clearly not going to work."

Except that was NEVER the case.  Born in '78, I believe I was still in elementary school when they abolished the Lord's Prayer (so late 80's?) and we had several students (couple Jehovah's Witnesses and several adamantly secular families) who were exempted from it and no-one ever batted an eye.