FILE in small claims or family court?

What is the name of your state? OHIO

My divorce decree states that I supply health insurance and that me and my ex split %50 anything that is not coverd by the medical insurance for our 2 minor children.

*The mony owed is a little under $50.
*The medical care they recived was in the same town in which I and the children reside.
*My ex lives in another state (Michigan).

If he does not pay me, do I file in small claims or family court to get my money.What is the name of your state?

Must be dealt with in a Motion to Show Cause

You have to deal with that as what it is, contempt of a domestic relations court order. Depending on how your order is written, you might even get the opposing party to pay your attorney's fees if you prevail.

By your answer it sounds like I would have to go to the family courts, is that correct?

Small Claims court cannot enforce a family court order, so yes, you have to deal with family court issues in family court.