If people value their childrens faith, then that's the stupidest idea I've ever heard.
The very instant the subject of evolution vs Genesis comes up the question will become "is there proof of God". This will happen in a government run school away from parents and church leaders. Its guaranteed that some, perhaps many, young skulls full of mush will decide at a teachers direction that God doesn't exist.
Like trying to convince a child that has figured out Santa Claus that he really does live at the North Pole. Trying to restore the faith of a child after they "get it" will never happen.
Leave science to scientists. Leave discussions on the meaning of Genesis in church.
Won't help. This is one of those topics where otherwise stalwart conservatives become mush-minded liberals, insisting that we should "let the children decide." They're apparently unfamiliar with "Lord of the Flies."