Closet studio storage-- this is similar to what I want to do with my office/craft room. Remove the closet doors that slide and put all the supplies and things in there with some nice storage/organization setup.
Instead of numbers write the color word on the bottles. Sort pom-poms by color. Empty each bottle and count the pom-poms. Then record how many pom-poms were in each bottle. Add the two colors together for addition practice.