"Defendants note that Wesley's babysitter, Judy Harper, testified that Wesley's favorite book in kindergarten was 'Brown Bear, Brown Bear.' Defendants contend that the Bible is really Plaintiff's favorite book." Busch v. Marple Newtown School Dist., 2007 WL 1589507 (E.D. Pa. 2007).
I should say that I'll be the first to admit that I've been exposed to a limited set of small children, and preferences may be very different in more devout households. Still, beating Brown Bear, Brown Bear strikes me as mighty hard, and I somehow doubt the Bible is up to the challenger.