Great question -- they're lucky to have a principal who is so concerned about the well-being of the organization. The work-around for poor financial records is to incorporate the group. The IRS considers an organization to be new as of its incorporation date. That means you would only have to submit financial data with your 501c3 application from that point.
It's a great idea to find someone to help -- is there an attorney in the school community, especially one with experience with nonprofits, who might help? Are any nearby PTOs 501c3? Maybe someone who has been through the process can act as an advisor. As far as signatures, the IRS is concerned about out and out fraud -- setting up dummy corporations, etc. Signing a 501c3 application or EIN request doesn't make the signer responsible for the group in any long-term way.
Another option is to put the PTO entirely under the school umbrella -- run the money through school accounts and make it a committee of the school. That takes away autonomy from the group and it isn't always the best situation, but it is a viable option that would allow the group to operate without applying for 501c3 status.
Good luck! Please let us know how it goes!
- Craig
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