How to Make a Homemade Lava Lamp – After School STEM Activities

By Heather Smith

homemade lava lamp. banner image

Years (and years) ago I took a Science for Teachers class in college that took place in a lab. All of us loved this class because it centered on hands-on science experiments that made learning fun.

Now, as a mother to a 7 and 9-year-old, I try to bring some of these hands-on activities to my home. After school can be filled with video games and Facetime, or I can help fill it with (learning) fun.

The following is one of my favorite experiments we did in the class. I hope you and your children enjoy it as much as we did!

Homemade Lava Lamp

Homemade Lava Lamp. Step 1. WD-40 can with soda water You will need:

  • Empty plastic or glass bottle with screw on lid
  • WD-40 & paper towels
  • Water
  • Oil
  • Food coloring of choice
  • Alka Seltzer (Quick tip: If you don’t have Alka Seltzer, you can use denture-cleaning tablets like we did here. It’s the same concept, just not as strong.)

First, we have to remove the glue from the bottle. To remove the glue, fill the bottle with very warm water and allow it to sit a few minutes. At this point, you should be able to scrape larger pieces of gunk off with your fingernail. Spray WD-40 on the rest of the glue and rub with the paper towels. This usually gets the bottle mostly to completely clean. Homemade Lava Lamp. Step 2. Peanut oil with bottle of soda water.

Fill the bottle a little past 1/2 full with the oil. Vegetable oil works great, but we improvised with vegetable oil.

Homemade Lava Lamp. Step 3. Mixed oil and water.

Fill the remainder of the bottle with water leaving at least an inch between the top of the water line and the opening of the bottle.

Homemade Lava Lamp. Step 4. Add drops of food coloring.

As I mentioned, we used denture-cleaning tablets because we had them on hand. They are not as strong as Alka-Seltzer though, so use that if you have it. We used an entire tablet of the denture cleaner. You will only need 1/4 to 1/2 of the Alka-Seltzer tablet.

Homemade Lava Lamp. Step 5. Red Color Added.

Add your tablet and replace the lid. Then sit and watch the show!

blue bottle experiment

It’s fun to try different colors of food coloring, different shaped bottles, different oils, less water and maybe even less/more food coloring. Be sure to ask your kids to observe what’s going on and take note of the reactions. Ask them questions such as why they think the two liquids separate.

If you’re looking for even more after school enrichment activities, head over to your local Sylvan Learning Center. They’re the perfect place for your little ones to have fun (while learning) after school!