Not a silly question at all. This isn't the kind of stuff most of us bump into on a regular basis.
First of all, does your group have a tax id number of its own? If you're not sure, go to the bank and find out what number was used to set up your account (ex: someone's personal SS#, the school's tax id #, the PTO's own tax id #).
If you find out that your PTO has its own tax id # (it would have been issued by the IRS based on someone filing form SS-4 in the past), then you can call the IRS and ask if the organization is a registered 501(c)(3). If your bank account doesn't reference a unique PTO tax id #, then it's highly unlikely that your group is 501c3.
You'll often hear two different figures quoted, $5000 and $25,000.
A general rule of thumb is that if an organization brings in $5000 or more each year (gross - everything - not what's left after expenses), they should formalize their structure by applying for 501(c)(3) status.
I've been told that if you AREN'T a 501(c)(3), then you are simply a business and should be filing a business return. However, most groups in that boat operate "off radar" and just file nothing.
If you ARE a 501(c)(3), then you must file an informational return (990 or 990EZ) if you make more than $25,000 per year. Many organizations voluntarily file this return even if they make less. (We do.)
Now all that is with the Federal government (IRS).
What you file with your State depends on your state's rules. Many of us - 501(c)(3) or not - pay state sales tax and file those forms each year. Our state doesn't have an income tax, but that might be an issue you should check into.
All I can tell you is that our PTO does not file any IRS paperwork either. I would guess if you do not have tax exempt status you don't have to file with the IRS.
I am the new PTO Treasurer for the upcoming school year. The school is an Elementary school in Indiana. I know from prior board members that we have to have our records audited every year (on a school year basis). I have also been told that there is no government filing required? Could this be true? Under what circumstances does a non profit group such as a PTO that does fund raising not have to report that? It seems unrealistic based on my career experience.