They’re mesmerizing, colorful, and make any room look retro. But lava lamps can also be a great way to teach your child about science. This homemade version won’t look exactly like the one in the store, but, then again, not many kids can say they’ve made their own lava lamp!

What You Need:

  • Empty and clean 16 oz. plastic soda bottle
  • Soda bottle cap
  • Vegetable oil
  • Food coloring
  • A large Alka-Seltzer tablet
  • Water
  • Flashlight (optional)

What You Do:

  1. Fill the bottle 3/4 full with vegetable oil. Add water to the remainder of the bottle, almost to the top but without it overflowing. Add 10 drops of food coloring, to make the solution appear fairly dark.
  2. Cut the Alka-Seltzer into 8 pieces. Drop one of the tiny pieces into the oil and water mixture. The mixture will start to bubble.
  3. Wait until the bubbling stops and add another piece of Alka-Seltzer. Continue until there is no more Alka-Seltzer, and the bubbling has completely stopped.
  4. Screw on the cap of the soda bottle. Tip the bottle back and forth and watch the wave appear.

The reason this homemade lava lamp works is because the tiny droplets of liquid join together to make one big lava like blob. Place a flashlight with a bright beam under the bottle to illuminate the bubbles for maximum visual effect.

 

By Mike Calhoun

Mike is a 20-year veteran science teacher, and runs an online business (www.scienceinabag.com). Over the years Mike has studied trends in science, education, and finance, conducting research, developing programs, and writing articles on these topics.