Wave Maker

This is a simple project with a scientific lesson about density and lots of fun to play with too!

Clear, empty 2 liter plastic soda bottle
Vegetable oil
Food coloring
Water

Start with a clear, clean empty 2 liter plastic soda bottle. Fill halfway with water. Add drops of food color to desired color (twist top on and shake to combine color). Adding more color if necessary. Any color will do we used blue (like the ocean) and we recommend to stay away from yellow because the oil is already yellow. Add vegetable oil to fill (all except about an inch on the top). Seal bottle tightly with cap.

You are now ready to experiment. Swirl the bottle while it's standing up or lay it down on its side and rock back and forth to create "waves.” You will find many interesting things to do with it. Try creating large bubbles by turning the bottle top over bottom a few times. Really shake it up to create millions of tiny bubbles. Look into the depths of the bottle when it has so many tiny bubbles with an "unfocused" gaze to get a holographic type effect. It also really looks great when lit from behind. Hold it up to the window on a sunny day to get an even more colorful effect.

Sometimes the oil gets a little cloudy when you've been playing with your wave maker a lot. Just let it sit still for several hours or days and the oil will eventually return to normal.