The state office may or may not have your bylaws on file, depending on whether or not they were submitted to them. You don't necessarily have to spend all of your funds, but rather you can transfer them to another 501c3. It may not be in your best interest to throw away your funds on things your group doesn't need. If you can't find a way to keep them for the new parent group you are forming, then consider transferring them to an organization within your school (boosters club, student council, etc.).
Well, I think you're doing it right. Make sure you spend down your PTA funds to basically zero before you even call the PTA. I'd also recommend that you start your PTO paperwork now. Incorporate your PTO and get your nonprofit status going now. You should be able to call the state and ask for a copy of your bylaws without telling them you're leaving.
I really need anyone's help. I'm secretary of a PTA that has voted to disband and become a PTO and I need to now where to go and get this done formally. We don't have a current copy of our by-laws and we want to do this right. Can anyone HELP me. Please either answer her or email me. Thank you. HELP