You'll get tons of ideas if you google it. My son had a sports party this summer. we made the invited look like tickets and had a baseball pinata. We did relay races, like kick the soccer ball around the cones, then throw a foot ball, then walk on a balance beam, crawl through a mesh tunnel, we didn't have a baseket ball but you could use that too. That was pretty good.
I tried playing a tossing game where we stood in a circle and tossed a soft baseball across the circle and everyone introduced themselves. I think my group was to small to make that work well. only 7 kids.
good luck and have fun.