I introduced first graders, as a FIRST 1st grade project, to overlapping by reading Jack Prelutsky's poem "Bleezer's Ice Cream". They loved this poem!
We talked about their favorite flavors, and then I demo-ed on the board. We discussed the notion of pattern, and how you could very simply create the cone pattern by following the lines of the upside-down triangle shape one way, and then reversing the lines to follow the other way. Overlapping lines made a diamond pattern!
I showed how you could draw one scoop overlapping another, and how you could illustrate that by erasing where the next scoop overlapped. We also discussed the patterns you could create by making toppings. We drew in pencil, outlined in Sharpie, and painted the background in tempera cake. Every one was amazing!