When I was a boy we used to look for particularly salacious or gross stories in the Bible and talk about them on the playground at recess.  My favorite one is the bread that God orders Ezekiel to bake - by cooking it over human poo.  We look at the Old Testament purity laws and what they were really meant to inspire in the People of God.  We look at what they mean for us today.  We consider how we can be "pure" in the eyes of God - in a spiritual sense.