For this fun, pseudo-science activity, you'll need:

Empty water and/or soda bottles
Food coloring
Cooking oil
Glitter
Small toys
Beans or pasta
Whatever else you want to add
And a hot glue gun to secure the bottle lids

Fill a bottle with water and food coloring. Add a little oil and watch what happens! Then, fill other bottles with water and glitter or water and small toys or dried pasta or beans.  Use them for a science idea, a musical instrument or set up a bunch of bottles, grab a ball and start bowling!