Most courts prefer to keep continuing jurisdiction when either the child or one the parents still reside in that state. If your divorce decree states you must notify the other party if you move (I’m almost sure it did), then you are in contempt. Also, your request about the school access does not sound reasonable. A parent, regardless of which party has custody, has a right to certain records and basic information about their child.
This reply is provided for information purposes only and does not represent legal advice or an attorney-client relationship.
The state that has jurisdiction, where the contempt motion has been filed is very unlikely to relinquish the case to the other state. If you have joint legal custody the mother cannot keep you from speaking to a teacher. You should share her actions, and attempted actions with your attorney so he or she can advise your judge, and try to move for for a change in custody.