What expenses are/are not covered by child support? Is there anywhere this is in writing?

Question

My, ex is always wanting money above and beyond child support for everything. She has an impression that anything above $50 is not covered by child support and should be split. This has included, clothes, sports activities, School supplies, Birthday parties, etc. Normally I help out when it comes to sports, birthdays and such but it's it's extremely aggravating when she expects it, rather than be thankful when I do split costs. She even asks me in front of the child, so that I won't tell her no. When we went to ODJFS, they explained that any money given outside of their system (excluding medical out of pocket) is considered a "gift". 
In our case, we have shared parenting and were never married.  I keep my son every weekend (Fri-Sun). She currently makes more income than I do, however, due to our past in which she has stolen from me, I don't trust her with money as I can't be sure if it's going where she says it is. It would be great to have what is/isn't included when dealing with her

Joseph Jaap · Answer

You are only obligated to pay as child support the amount the child support order states.  That money is to be spent by her in support of the child, but ODJFS does not check up on how she spends it. You do not have to provide any additional money to her.  But, if the child goes without because she spends it on other things, then it is up to you whether you want to provide additional "gift" money.  Perhaps you can pay child expenses like sports directly, so she can't use it for something else.  You can apply to change the amount of child support if circumstances have changed since the time it was initially determined.

Q: What expenses are/are not covered by child support? Is there anywhere this is in writing?