There are a few different Magnetic Mosaic sets on the market that would be good for kids. The basic idea is that you have a board with magnets in it, and then you can stick little metal pieces to it. The pieces usually come in different colors, so kids can create designs and pictures. One popular set is called Magna-Tiles. These tiles are colorful and durable, and they create really cool 3D designs. Another option is the Picasso Tiles set. These tiles are also colorful and durable, but they’re designed to look like classic paintings by Picasso.