The most fun we've come home with was a Shofar project from Hebrew nursey school. A two foot length of hose was looped and secured with electrical tape ( in multiple colors) then a funnel was secured in one end and a kazoo in the other. I'm pretty sure they hung ribbons on the loop as well... It makes for a very loud kazoo band.

You can also use the cut off ends of two liter bottles instead of funnels ( cover the cut ends with more tape cause they have sharp edges).

If you want real musicality you are out of my league, but these were fun.

Tinker