I don't have time to read other responses, so I apologize if mine is repetitive.
Schools have a lot of discretion, in how they handle things with divorced parents. I have heard of/experienced cases where school employees refused to follow court orders, because they were siding with one parent, or because the orders conflict with the school's standard policy; AND cases like yours, where school employees were all too cooperative, when perhaps they should have waited to act, until they received direction from a judge. In either case, people who are trained to educate children - not to interpret legal nuances - are being asked to do the latter. And they're not really accountable. If either parent is displeased with how the school handled something, their legal recourse is usually to take the other parent to court and argue that what he/she asked of the school was improper. Usually, you're not going to get far, complaining to anyone about the school employees themselves.
If it's obvious from the info. on the tuition contract that the credit card/bank account providing tuition does not belong to your ex; and if it's common knowledge that you and your ex are divorced; then it would have been more appropriate for the school to redact that information before giving your ex a copy of the contract. He should have the right to see any papers relevant to his child's education, regardless who's entitled to choose the school - especially if those papers verify how much is paid for her tuition. But obviously he has no right to know your parents' credit card or bank account number, nor could he provide any plausible argument for why he needs that.
But that info. was carelessly given to him and can't be taken back. Unless you're worried that he'll try to fraudulently charge his next ski trip to your parents (if he does, you might consider suing the school!), then you need to let it go. He sounds petty and bitter. I know that's annoying. I also know it can make you feel threatened, just knowing someone's looking for any reason to take you back to court and try to change things in your life you've come to rely on. But you're not married to your parents and they have no financial obligation to your daughter. Unless you work for them and you're concealing your income from Family Court, they're allowed to give you gifts, like paying for your daughter to attend a better school than you could afford; or covering your ex's share of her medical bills when he's late paying it. That shouldn't affect how much he pays in C/S, even if he wishes it did.
The only problem would be if you receive "credit" for tuition and/or plane tickets that you don't actually pay for. In other words, if his complaint is basically, "Her parents do so much to support the child I fathered, that I shouldn't have to contribute anything," then everyone - including your judge - will see him for what he is and dismiss his arguments. But it might get more complicated if his complaint were: "My annual earnings are so small that it's hard enough supporting myself. Anything I pay in C/S is a hardship. Even though RN2Bmommy earns almost double what I do, when the court calculated C/S, it plugged in equal incomes for us, because she reported spending half her income on tuition and our child's plane tix to visit me. But her parents pay for those things and she's never actually spent a cent of her income on them. So, I want the court to recalculate."
If you did get credit for paying for things your parents actually pay for, I'm not judging you. But, now you need to pay attention to how you will look in court, if your ex takes you back. If you behave as though you're desperate to keep your ex from finding out what your parents pay for, it will look like you're cognizant of doing something wrong, that you feel the need to hide. It's better if you can truthfully say, "I reported my income honestly. I reported my daughter's expenses honestly. At no point have I tried to misrepresent or conceal anything from my ex. I just honestly did not think that help from my parents was relevant to my financial declaration."
Edited by VocalMinority - 3/21/11 at 1:37pm