Making "lava lamps"

When the girls came over last weekend, we made homemade lave lamps.  They aren't really lamps as they provide no light, but the bubbling blobs of color do look something like lava lamps.
These were fun to do and if you have young kids around, they would probably enjoy doing it too!

What you need to do this is:
empty bottles - we used water bottles, you can use glasses, mason jars or anything that's clear that you are able to see into.
vegetable oil
water
food coloring
alka seltzer tablets



There are no specific measurements, but you use twice as much oil as water.
I put the oil in each bottle and the girls put in the water.

 Here is Alaina adding water to her bottle.  After the water is added, let them watch how it doesn't mix with the oil and it separates.

 Here's Ruby putting in drops of food coloring.   (on our first attempt at this, Ruby tipped her bottle over, pouring oil, water and food coloring all over the table.  After that we got paper plates to out underneath for a little protection, just in case)

You can see the water on the bottom with the oil on top of it.  If you look close, you'll see some drops of food coloring sitting in the water, not mixing up.

Now it's time for the alka seltzer tabs.  Break it in half and drop both halves in, let the bubbling commence!

Alaina had green, Ruby had pink although it turned out kind of red.  The bubbles float up and down.  Once it stops, you can put in another alka-seltzer and start again!