We did Square 1 Art last year and it was amazing - the kids loved it, the families loved it. The products are great quality and it's a real feel-good. We didn't make a TON of money, but we are a low-income school so taking that into consideration we did quite well.
I started a school fundraising company a couple of years ago, based on a creative graphic art project that I did for my son's elementary school, that was extremely well received by our parents. The website is schoolartgraphics.com and we finished a redesign, making it even easier for schools to have a lucrative art (or graphic art) fundraiser. I would love to get some feedback from PTO members on our new program!