What exactly should child support cover?

I have been contacted almost daily about many different items that my ex claims I need to pay half of. My ex seems to think that if the item doesn’t fall under food, clothing and shelter, then she needs to have payment for it. I have faithfully paid my portion of out-of-pocket medical expenses as written by the court order. I am being asked to pay for car repairs, band fees, school fees, pictures, school supplies, etc… I don’t mind doing my share of the bills for the two children, however, the daily contact about nickel and dime payments is getting ridiculous. I already pay close to $1200 per month in Child support, and I think that should cover some of these items. I am sure there is not a cut and dry list of items covered by childsupport, but I am looking for any kind of clarification that I can pass on. Thank you.

You do not have to pay for any of the items you mention unless your order specifically states that you have to share in such expenses.