don't know if this has already been posted since i havent read through the whole thing yet (lazy me), but--
i work at a preschool and we do texture painting, which is shaving cream + glue + paint.. its the same thing except yours looks fifty times cooler with all the different colours

anyway, i was thinking, if you add glue to it, it might hold shape a bit longer.. or does it actually work with JUST shaving cream and food colouring?