By law, you must donate them to another 501(c)(3) organization - could be your PTO or another organization.

Well if you can not sell them just give them to the students or donate them.

Sell them to the PTO for a dollar. Not each, a dollar in total. You could sell them for what the PTA paid for them, but really, what's the point? Then it's juts more money for the PTA to spend down.

We are currently in the process of changing from a PTA to a PTO. We have several t-shirts, car magnets, shopping bags, etc. that were bought with PTA money, but not yet sold. Is there a way to keep those items and transfer them to the PTO for the PTO to sell? Any advice/suggestions would be helpful. Thanks in advance.