These Easter egg bath bombs are the perfect combination of festive craft and fascinating science! Make them with your kids using easy-to-find ingredients, and then take them to the tub for a fun-filled bath time!
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Easter is around the corner, and I’ve got an egg-celent (I know, I blame my dad for teaching my puns) DIY project for you today! This one requires a little advance planning (nothing too crazy, I promise), but the little bit of effort will yield LOTS of fun.
We’re making Easter egg bath bombs!
Bath bombs have been all the rage for the past several years, and my kids think they are so cool, so I thought it would be fun to make our own.
And what better mold to use for shaping your bath bombs than a plastic Easter egg?! You probably have them on hand already, they are the perfect size and shape, and they make for a festive Easter activity.
Where STEM and art meet
What I love about this activity is that it’s the perfect combination of crafting and science. Kids will love mixing the ingredients and layering colors to create their “craft”, but once they plop that bath bomb in the water it becomes an awesome science exploration activity.
And since your kids are sure to ask…
Why do bath bombs fizz in water?
Answer: This cool science trick works because of the chemical reaction that takes place between an acid and a base when you add water. Baking soda is the “base” and citric acid is the “acid.” (This is the same reaction that occurs in the popular baking soda and vinegar volcano experiments, except that we’re using citric acid as the acid instead of vinegar.) When the acid and base combine with water, the chemical reaction releases lots of bubbles of carbon dioxide gas, and you get to enjoy all the fizzy fun!
Bonus fun fact: If you’re wondering why the recipe calls for cornstarch, it slows down the reaction so it takes several minutes instead of just a few seconds. If you want a more detailed explanation, this article discusses the molecular structure of the ingredients we’re using.
Let’s have some fun!
Below is a quick overview of what we’re doing, but scroll down farther for the complete recipe and full tutorial.
Step 1: Gather your ingredients.
Step 2: Mix together ingredients. Divide them into bowls and mix in food coloring of your choice.
Step 3: Press the mixture into the molds. Close tightly, and let dry for several hours (overnight is best). Then carefully remove the bath bombs from the egg molds and you’re ready for bath time!
I made all sorts of mistakes in learning how to make these bath bombs, so now you don’t have to!
First, I read some recipes that recommended putting the eggs in the freezer to solidify. I tried this, and it was a BAD idea. It worked perfectly for getting the eggs out of the molds, but as they thawed, they began to sweat and the condensation made a weird bubbly texture on the bath bombs (presumably the moisture was activating the chemical reaction just a tiny bit). They were still functional, but they were NOT pretty. Just leave them at room temperature. It worked much better.
Second, if your bath bombs crumble when you take them out of the molds, it probably means you didn’t add enough water when forming them. We had 2 of our 7 eggs break the first time. The good news? You can totally get the mixture damp again and press it back into the molds. So, if at first you don’t succeed, just try again…maybe with a few extra spritzes of water this time. No harm done. Our failure eggs totally worked the second time!
- 1 cup baking soda
- ½ cup citric acid
- ½ cup corn starch
- 1/4 cup Epsom salt
- 1 Tablespoon carrier oil (*see note)
- 1 teaspoon water (water in a spray bottle ideally)
- 10-15 drops of essential oil
- Food coloring, if desired
- In a mixing bowl (some sources suggest NOT using plastic), combine baking soda, citric acid, cornstarch and Epsom salt.
- Drizzle oil over mixture and add desired amount of essential oil (start with 5-10 drops and add more if needed). Mix until well combined.
- While continuing to mix, lightly spray mixture with water a few times (set spray bottle to mist, not stream) until you can squeeze the mixture together in your hand and it holds its shape. If you don't have a spray bottle, you can just drizzle the water over the mixture, but mix it quickly and avoid dumping it in at once or you will start the fizzing reaction.
- Scoop into each side of a plastic Easter egg (or any other mold) and pack firmly. Make sure the mold is all the way full, then close tightly. Use tape or a rubber band to secure the egg and keep it closed.
- Let sit for at least 2 hours, or overnight, to dry. Then, carefully open the egg and remove the bath bomb. It may take a bit of work to dislodge the bath bombs from their shells. I loosened the sides with a butter knife and then twisted the eggs to get them out.
- Drop in the bath and enjoy the fizz, or package up to give away as gifts!
There are lots of different options for what kind of oil to use. In my first batch I used baby oil because I had some leftover from another experiment. It worked fine, but the scent competed with the essential oil scent, so I wouldn't use it again. I recommend coconut oil, or any other carrier oil (like almond, jojoba, or argan oil). I've even seen other recipes that use olive oil, so feel free to try it! Just pick an oil that you like the smell of...or that doesn't have much fragrance.
Also, several of the ingredients in the recipe are optional (including the oil). The base recipe is just baking soda, citric acid, corn starch, and water. Everything else is just added to make a more soothing and fun bath. So, feel free to leave out the other ingredients if you don't have them on hand!
Frequently Asked Questions:
Where can I buy citric acid?
You can find it easily on Amazon (here’s the citric acid I bought for this recipe). You can also find it in many grocery stores with the canning supplies, or in craft stores with the soap-making supplies. It’s more common than you might think.
Can I make bath bombs without citric acid?
Yes, BUT the substitutions I researched just didn’t perform as well. This video shows the results of three other options. Ultimately, I highly recommend sticking with citric acid.
What kinds of oil can I use for bath bombs?
I recommend coconut oil because it’s easy to find and smells good. But if you want to get fancy, you can use almond oil, jojoba oil, grapeseed oil or any other carrier oil. I’ve even seen recipes that use olive oil, so feel free to try it! Just pick an oil with a light scent, or a scent you enjoy because it will come through in your bath bombs (It’s for this reason that I don’t recommend baby oil…I just don’t like the smell).
Have you made bath bombs before? Drop any tips YOU have in the comments!
Looking for more fun Easter activities? Try these: