Make a volcano using a plastic soda bottle and air-dry clay. Place the volcano in an extra large tub away from anything that might get splashed. Pour some tonic water -- water containing quinine, which is fluorescent -- into the bottle. Turn on a portable UV light and turn off the regular lights. Point the UV light at the volcano, making sure not to shine it in anyone's eyes. Instruct a child to insert a whole package of Mentos into the bottle and to pull back quickly. The resulting lava should fluoresce blue.
Make a papier-mache volcano. Paint the outside of the volcano with one color of phosphorescent paint. Using another color of phosphorescent paint, paint on lava flowing down its sides. Have a child hold a bright flashlight over the volcano to charge it. Have another child turn off the main light. This project can be used in combination with a lesson explaining phosphorescence.
This project shows the inner workings of a volcano. Shape a cross-cut model of a volcano, using several varieties of polymer clay. Paint each color of clay with a different color of glow in the dark paint. To view the model, place it under a bright light in a room with no windows or with the blinds closed. Then turn off the light and watch the volcano glow.
Work with the kids to craft a volcano out of papier-mache around a mason jar. Paint the volcano with glow in the dark paint. Pour some water into the jar and charge the volcano under a bright light. Place dry ice into the jar and turn off the lights. The volcano will smoke. Use this model to teach about how volcanoes emit smoke before erupting and to introduce the concept that volcanoes may erupt at night.
Fill a a large, clear bowl partially with water and mix in glow powder. Place a balloon into the bowl that has a straw stuck into its opening and pour a layer of oil on top. Cut a Styrofoam plat into three sections. Cut out a semicircular section from the rim of one section for the straw to go through. Charge the water with a bright light and turn off the lights. Inflate the balloon with the straw to see what it is like when lava breaks through the Earth's crust.