My kids love anything fizzy. No matter how many times we do it, a fizzing reaction still feels like magic to them.
These hatching dinosaur eggs hide a tiny dino inside a baking soda shell. Squirt on vinegar and watch them fizz open.
How to Make Fizzy Dinosaur Eggs
Dinosaur STEM Challenge Cards
Get the printable3 heaping tablespoons baking soda per color
1 heaping teaspoon cornstarch per color
Water
Gel food coloring
Sandwich bags and gloves
Mini plastic dinosaurs
Vinegar, droppers and a tray
Mix the dough
In a bag, add baking soda, cornstarch and a few drops of food coloring.
Add water slowly
Add water a teaspoon at a time and knead until it holds together like damp sand.
Make more colors
Repeat for a few colors.
Shape the eggs
Wear gloves. Pack the mixture around a mini dinosaur and shape it into an egg.
Freeze
Freeze the eggs 2 to 3 hours to harden.
Hatch them
Set the eggs on a tray and let kids squirt vinegar on them until the dinos hatch.
Safety note
Keep vinegar away from eyes. Mini dinosaurs are a choking hazard for little ones. Food coloring stains, so wear play clothes.
The Science Behind the Fizz
Baking soda is a base and vinegar is an acid. When they mix, they react and make carbon dioxide gas, which makes the bubbles.
- More foam: Add a squirt of dish soap to the tray.
- Bath bomb version: Mix 1 tablespoon citric acid per 3 tablespoons baking soda and use melted coconut oil instead of water. Let them dry and drop them in the tub.
- Compare: Which color hatches fastest?
More dinosaur activities
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Write about your dinosaur discoveries with our dinosaur writing prompts.
The STEM cards include
- Dinosaur STEM challenge cards
- Instant PDF download, nothing is shipped
Perfect for
- Dinosaur units
- Preschool through 2nd grade
- STEM centers
Fizzy Dinosaur Eggs FAQ
Mix baking soda, cornstarch, a little water and food coloring, pack it around a toy dinosaur, freeze, then hatch with vinegar.
Freezing helps the eggs hold their shape until kids hatch them.
Yes. Add citric acid and use coconut oil instead of water, then let them dry.
Baking soda and vinegar react and make carbon dioxide gas.
More Dinosaur Activities
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