Try some lava in a cup

* A clear drinking glass
* 1/4 cup vegetable oil
* 1 teaspoon salt
* Water
* Food coloring (optional)

Making things glow in the dark

Have you ever wondered what makes certain things glow under black lights?

For this experiment you will need:

• a black light
• petroleum jelly
• a piece of paper

First we’ll use the petroleum jelly as a kind of invisible ink. Dip your finger into the jelly, then use your finger to write a message on the piece of paper. Use more jelly if you need to – but this probably isn’t the time to write a long speech! When you’re finished, wipe any remaining jelly off your finger. Have the black light ready, then turn off the room lights and turn on the black light.