Art project ideas or kits?

Tomorrow I'm going to my IL's. THey are having some families over with kids. Kids are between 2 and 6. My IL's have a pool, but not a ton of toys. I thought it would be cute to bring some other activity for the kids to do outside like some art project or something.
Don't have much time to shop around or research so wondered if there's anything I can get at AC Moore, Michaels, or Hobby Lobby. All are close to me.

Any kits or ideas the kids can do outside? It's supposed to be beautiful, but figured it's something to keep them entertained too when they're not swimming.

Thanks!

Art project ideas or kits?

Stepping stones for the garden. There are usually three in a pack. Really fun to do outdoors but it needs to dry overnight before taking out of the mold.