Clay is always a big hit. I used Crayola self-hardening clay in this project. The Crayola brand worked well, but you have to make sure the students add a small amount of water to keep it moist, and they need to make sure all the cracks are smoothed out (this will keep them from cracking more when they dry). It was around Valentines Day, so I allowed this class to make a heart to either keep for themselves or give to someone. We talked about the tradition of Valentine's Day and the heart symbol. I also showed them a picture of a real heart to help them understand that this was a symbol, not the same shape as a real heart. I also showed them the artwork of artist Jim Dine, and we discussed how he used the heart shape in his artwork.
It was easiest for the girls to make a ball first, then start to create the shape. I also gave them a lot of different tools to etch shapes and patterns into the surface. After the hearts were dry, they painted them however they wanted.