No, it's not a trick question. Sometimes one parent gets decision-making authority over the other, which can make a difference.
First, you have the ability to go back to the court and seek a Modification, stating that you would like to change the custody order, since your ex-husband has removed the child from his home. As part of that, you can ask the judge to give you the power to remove her from school and enroll her in the district near where you live. The fact that she's not currently living with her father will hurt him if he opposes the request. If you're paying support, that would also end it, and you may be able to get support from him, due to the change in circumstances.
You may also be able to negotiate with the father to simply agree to the change in custody (in writing). If you're willing to negotiate child support
, that may help - especially if he is aware that a judge may order him to pay you 20% of his income if you go back to court. As part of that agreement, he could sign something giving you sole decision-making authority.
Otherwise, if you're supposed to make decisions together, neither of you can unilaterally make changes to where she is attending school. It would be necessary to go back to court to show why the change is in your daughter's best interests if the two of you cannot agree. The fact that he has residential custody doesn't make a difference, because that's not the same as legal custody. Legal custody is the power to make important decisions, such as those regarding education, religion and health care.
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