The only problem I can see with integrating this into another class is that the students in my class were very well behaved. Bringing elastics into a class with a lot of behavior problems could prove to be problematic. Maybe for that activity different lengths of string could be used instead of the elastic. If I was going to build on this I would try to integrate some sort of drama into the class. It is the only part of the arts that I did not tap into.
Songs are another idea for helping students to learn math.
Overall, it was a very successful integration of the arts into mathematics.