Last year, my daughter had her birthday party at Painted Penquin in Vernon hills. She was 7. My nephew and another kindergarten friend of my daughters also had birthday parties there.
They all loved it. They get to make something and they get to bring it home. I don't remember if I did goodie bags for that birthday party - but for this one you don't really need to. :)
For an additional charge, they supplied the cake. It cost us less than getting one from our local bakery. It was not the best, but the kids wont really care. They can also supply soda.
Also, at the Vernon Hills location, they had a dinosour hunt. (I don't know if that is the exact term?).
Instead of picking out an item to paint, the kids get something that looks like a stone. They have tools to dig up dinasour bones. My daughter and her friends were watching kids next to them doing this and they were all interested in it.
Your son and his friends will like going to the Painted Penquin. Ask your location what they have available for you.
M.