This has garnered lots of comments along the lines of "Great, now schoolkids in TN can give answers based on Islam / Buddhism / Hinduism / FSMism and get full credit and there's nothing they can do about it! Be careful what you ask for, fundies! Hah hah hah!"
It does not work that way. Here's how it will work. Religious answers which will be acceptable, and more generally, religious challenges to school authority which will be acceptable, will be those based in Christianity, specifically fundamentalist Protestantism. And students who profess other beliefs will be even more ostracized than they already are. This is what the sponsors of the bill wish to achieve, and if the bill becomes law and survives the inevitable court challenges, it is what they will achieve. To think anything else is naivete of the highest and most dangerous order