If you want to encourage kids to draw tall shapes, it helps to have paper cut to match. I turned standard 18" x 24" watercolor paper into 18" x 6" panels for this project and it worked really well.
1. Students discussed all the different ice cream flavors they could think of. The point was to realize how many different colors ice cream comes in these days. They sketched in pencil a cone with as many scoops of ice cream as they could fit.
2. To help keep the watercolor from spreading, all the lines with were traced in crayon.
3. The scoops and background were painted in with watercolor paint.
4. After the paint was dry, all the lines were traced again with a black permanent marker. Little spots were traced as specks of fruit.
Class Follow Up: I had a small amount of non-hardening clay on hand, and I gave each student a grape-sized piece and challenged them to see who could make the smallest ice cream cone. The kids loved it and focused on the task, rather than comparing who got the most clay, etc. And some made incredibly tiny shapes!