🍀 Magic Leprechaun Coins: A St. Patrick’s Day STEM Activity

Happy Saint Patrick’s Day! In this fun STEM activity we are blending a little science with a bit of fun seasonal magic This simple St. Patrick’s Day activity invites children to explore, create, and wonder as they reveal their very own “leprechaun coins.”

With just a few kitchen ingredients, your child can turn ordinary coins into fizzing, foaming treasures!

What You’ll Need

Coins (any kind will do!) (Plastic dries quicker!)

Baking soda

Water

Green food coloring (optional, but festive!)

Vinegar

A dropper or small pipette

A small bowl for mixing

🍀 Preparing the Leprechaun Coins

Begin by mixing baking soda with a small amount of water until it forms a thick paste. Add a drop or two of green food coloring if you’d like to give it that St. Patrick’s Day charm.

Invite your child to coat each coin completely in the paste, placing them on a plate to dry. This step feels a bit like crafting “hidden treasure.”

Allow the coins to dry for a few hours, or until the coating is hard to the touch.

🧪 The Magic Reveal

Once the coins are fully dry, it’s time for the magic.

Pour vinegar into a small container and add a few drops of green food coloring for an extra festive touch. Using a dropper, let your child slowly drip the vinegar onto each coin.

Watch closely…

The coins begin to fizz and bubble as the “magic” happens before their eyes!

🌈 What’s Happening?

This magical reaction is actually a simple chemical reaction between baking soda and vinegar. When they meet, they create carbon dioxide gas, which causes all the fun fizzing and bubbling.

It’s a beautiful, hands-on way to introduce early chemistry concepts in a way that feels playful and memorable.

🍀 ways to extend the magic~

You might invite your child to:

Count how many drops it takes to reveal each coin

Predict which coin will fizz the most

Describe what they see, hear, and feel

This turns a simple activity into a rich sensory and learning experience. These “leprechaun coins” are a sweet reminder that even simple moments can hold a bit of magic. 

Enjoy! Chloe