I should clarify, if the dck are in fact sick (what I determine sick based on my Contract) and I tell them they cannot attend that day, the parents still have to pay.

If I am sick and give the parents a choice, then I charge if they attend and do not charge if they keep dck home. Since I did after all give them a choice. It wouldn't really be a choice if I still charged them. In my opinion. Once again everyone has different opinions and you have to do what you feel comfortable with.