I've used Crayola's modeling clay for years at home with my son and at work as an arts educator. This non-drying clay is easy to use and comes in array of colors. The clay is easy to mold and soft enough for young children to use. That said, it is still sturdy enough for older children to enjoy. This product allows kids to sculpt three-dimensional projects with ease. My son has never had a problem pulling it apart or using it to sculpt with.
One of the pros to this product is that it doesn't dry out. If you are looking for an air dry clay that hardens after the art-making is over, this isn't the product for you. Crayola's modeling clay stays moist and doesn't harden when left out. This makes it easy to reuse. If your child doesn't like what he's made or doesn't want to save it, you can pack up the clay in a baggie and use it again.
Another positive part of this product is the price. Compared to other clays, it is low-priced. This makes it a great value for what you get. My child gets hours of fun for a very reasonable price.
The one drawback to this clay is that the colors tend to rub of on the child's hands and may stain. While any craft project can get messy, this product has stained some of my light-colored clothes. It does eventually wash off of your hands, but the sticky nature of the clay makes it somewhat tricky to scrub off right away.