How to make a lava lamp

This was the "experiment" we did yesterday; it kept an 8-year old boy's attention for a lot longer than you'd think. Get a glass or plastic jar or beaker; tall and thin is preferable to short and squat. Fill it one-third full with water and add food coloring. Red is what came with the kit, and it looked good, but you can go for a favorite color if you want. Fill the jar to two-thirds full (another third) with cooking oil. Then, pour 1-2 tablespoons of table salt on top of the oil. As the salt settles to the bottom, it takes some oil down with it. The oil bubbles slowly work their way free of the salt and rise to the top. It took 15-20 minutes before all the bubbles stopped, and we watched every, single, last one. Definitely better for the brain than Sponge Bob, in my opinion!