Ocean in a bottle

Ocean waves in a bottle.

Use one of your old salsa jars or something.  That is what we used anyway. :)  You could also get a glass bottle with a cork.  Fill it half way with water and add blue food coloring.  Next fill it up the rest of the way with vegetable oil.  Let sit on it's side a couple minutes.  Then you can move it around and twist and watch the waves in the bottle.