Let me clarify one point, if your PTO receives less than $5,000 gross income, the IRS doesn't expect you to formalize. But you are not
automatically non-profit or tax exempt - you are simply small enough, the IRS doesn't care.
But if you make MORE than that, they expect you to formalizing your organization. Filing for 501(c)(3) status is a common and important step.
Critter is right, there is a lot of information on this forum to help you. The basic steps are (and, as an existing organization, you've probably already done some pieces):
- Request a new EIN and open a bank account with the EIN
- Free, simple one page form (SS4). Can be done by mail, online, or by phone.
- Incorporate as a non-profit within your state
- This makes you an entity and reduces personal liability of officers/board members. You want to do this if you can. In most states, it's some boilerplate paperwork and a small fee ($25-$50). But there are a few where it's more complicated. If it's more trouble than it's worth, skip it.
- Create or adapt robust bylaws and adopt them (that also satisfy IRS).
- File for 501(c)(3) status (after incorporating) with the IRS
- This is a status federal that defines you as a charible organization.
- Benefits: provides credibility, allows contributions to you to be deductable, and exempts you from paying federal income tax on your fundraising income.
- Process: fairly complex application, plus $750 fee
- Apply for state sales tax exemption
- state often requires you to have your 501(c)(3) first
Simultaneously, you'll continue with the program side of your organization.