Lava lamps are a simple but fun science experiment for kids, using materials you probably already have in your kitchen cupboards. We've given these a Christmas twist by decorating them like reindeer and snowmen. Crafts are not my strong point, so I'm sure you can do a much better job with your Christmas lava lamp.
If you're searching for awesome science gifts, I've got some great DIY science kit ideas and ready-made science kit suggestions, too.
I also have a FREE Christmas Lava Lamp printable instruction sheet you might find handy.
Christmas Lava Lamps
Use my handy instruction sheet to make your very own reindeer lava lamp!
How to make a Christmas Lava Lamp
What you need
- A clear plastic bottle or jar
- Vegetable oil
- Food colouring and decorations
- Alka Seltzer or an effervescent vitamin tablet
Christmas Lava Lamp Instructions
- Fill the bottle or jar a quarter full of water, then add a few drops of food colouring.
- Fill up to (near) the top with vegetable oil. The oil and water should separate into two layers, with the water at the bottom and the oil sitting on top.
- Decorate your jar.
- Pop in half an Alka Seltzer tablet and watch the bubbles form. Add more Alka Seltzer gradually to keep the bubbles rising and falling.
Why do oil and water not mix?
See our original lava lamp post for a full explanation of why oil and water don't mix.
Why does oil sit on top of water?
Oil sits on top of water rather than beneath it because it has a different density than water. Water is denser than oil, so it sinks to the bottom.
Why do lava lamps bubble?
As the Alka Seltzer is added (this is made of citric acid and sodium bicarbonate), it reacts with the water to form carbon dioxide gas and sodium citrate. The carbon dioxide bubbles carry the coloured water to the top, giving the characteristic bubble effect.
More Christmas Science Ideas
Create a Santa themed lava lamp.
I also have some easy science ideas for the elf to bring, and some simple Santa STEM Challenges you might like!
Don't forget to check out my Christmas Science Ebook, containing 12 printable Christmas themed experiments and activities, perfect for this time of year.
New for 2022 is 24 days of elf ideas, all with a fun science twist! You might also like my ULTIMATE list of Christmas science experiments, which includes lots of free experiment instruction sheets and STEM gift ideas!
Last Updated on December 2, 2025 by Emma Vanstone
Nick says
This looks like a fun rainy day project to do with the kids. Thanks for the share! 🙂