You can make sieves for sand play by punching holes into pieces of heavy cardboard or small cardboard boxes, or into the tops and sides of Pringles Potato Chip cans. Even the smallest ones can add so much. If you don't live near a beach, you can often find bags of tiny seashells at craft or thrift stores. Well, this is a great way to use those up. I simply provide a small cup of water at the easel with several colors of chalk pieces.
Children dip the chalk into the water before drawing on their manilla paper flower cut-outs.
The pictures will have a deep rich color. If you're concerned about the chalk smearing, you can give the pictures a light coating of hairspray once they've dried.