st. patrick's day activity
Exploding Rainbow Gold Science Experiment for Preschool & Kindergarten
Looking for a hands-on St. Patrick’s Day science experiment that feels magical but still supports real learning.
This Exploding Rainbow Gold Science Experiment for Preschool & Kindergarten turns a simple baking soda and vinegar reaction into a colorful, fizzy STEM adventure your little learners won’t forget!
With just a few easy materials, students can draw their own rainbow, make predictions, and watch as their “leprechaun gold” comes to life.
It’s the perfect blend of curiosity, purposeful play, and early science exploration, especially during those high-energy March days when kids need something exciting and meaningful to focus their attention.
Rainbow experiments are always a favorite in our classroom, and you can explore even more colorful ideas here.
Watch the video tutorial below.
materials
Sandwich bags
- Permanent markers
- Vinegar
- Gold glitter
- Shamrock confetti
- Baking soda
purpose
- Explore cause and effect
- Safe way to observe chemical reactions
- Fun way to introduce the scientific method
- Explore early STEM concepts
- Supports visual learners with colorful materials
Why Kids Love This Exploding Rainbow Experiment
There’s something extra exciting about combining science with a little bit of St. Patrick’s Day magic.
As students draw their own rainbows, make predictions, and watch their “gold” start to fizz and grow, they’re not just observing a reaction, they’re actively participating in the learning process.
Hands-on experiments like this support early problem-solving, build curiosity, and give little learners a safe way to explore cause and effect through purposeful play.
The visual change inside the bag keeps even your most wiggly students engaged, making it a great choice for high-energy March days when you want meaningful learning without complicated prep.
When planning a full week of hands-on March activities, I like pairing simple science experiments like this with the St. Patrick’s Day STEM challenge cards so students can keep building and exploring throughout the day
directions
How to do the Exploding
Rainbow Gold Science Experiment
Draw a rainbow on a sandwich baggie using permanent markers
Pour 1/2 cup vinegar in a cup
Add gold glitter
Add shamrock confetti
Add 1.5 tablespoons of baking soda to a piece of paper towel
Fold the paper towel filled with baking soda
Quickly drop the paper towel into the sandwich baggie
Quickly seal the baggie, getting the air out while you do
Watch the reaction!
The baggie should fill with gas and eventually erupt-allowing all the gold treasure to come out!
The Science Behind the Exploding Rainbow
Even though this experiment feels a little like leprechaun magic, it’s actually a simple chemical reaction that’s perfect for introducing early science concepts.
When baking soda (a base) mixes with vinegar (an acid), they react together to create a gas called carbon dioxide.
As the gas builds up inside the sealed bag, it needs more and more space, causing the bag to expand and puff up.
Eventually, the pressure becomes too strong and the bag bursts open, releasing all that fizzy energy at once.
This exciting moment gives children a hands-on way to see how substances can change, making abstract science ideas easier to understand and remember.
Extension Ideas for Little Learners
There are so many simple ways to keep the learning going without adding extra prep with this science experiment. These extension ideas help reinforce early math, language, and observation skills while keeping the St. Patrick’s Day excitement alive.
Make Predictions First
Before sealing the bag, invite students to guess what will happen. Will the bag grow big or small? Will it explode quickly or slowly?Count the Shamrocks
Have students count the shamrocks before adding them to the vinegar mixture. This adds an easy math connection.Design Different Rainbows
Try drawing stripes, zigzags, or dotted patterns on the bag and compare which designs show the reaction best.Science Talk Time
Ask questions like: What do you see? What do you hear? What changed inside the bag?Leprechaun-Themed Follow-Up
After the experiment, keep the excitement going with a Leprechaun Scavenger Hunt where students search for clues to find their little Irish friend and continue the St. Patrick’s Day adventure.
Safety Tips & Teacher Notes
Because this experiment creates pressure inside the bag, a few simple safety steps will help keep the experience fun and stress-free for everyone.
Adult Supervision Required
Always have an adult present when sealing the bags and during the reaction.Step Back Once Sealed
After adding the baking soda packet and closing the bag, have students take a few steps back and watch from a safe distance.Use a Tray, Bin, or Outdoor Space
Setting the bags inside a plastic bin or taking the activity outside makes cleanup quick and easy.Optional Safety Glasses
Not required, but they can make kids feel like real scientists while adding an extra layer of protection.Remove Extra Air Before Sealing
Gently press out excess air as you zip the bag to help control how quickly it expands.Have Paper Towels Ready
A little fizzing mess is part of the fun, but keeping wipes or towels nearby helps everything run smoothly.
The Exploding Rainbow Gold Science Experiment is such a simple way to turn an ordinary day into a hands-on STEM adventure your preschool and kindergarten students will remember long after the fizz settles.
With just a few materials and a splash of creativity, little learners get to explore real science concepts while feeling like they’ve discovered a bit of leprechaun magic along the way.
Activities like this make it easy to blend curiosity, movement, and purposeful play into your St. Patrick’s Day plans!
If you love this experiment, you should check out these Rainbow- and St. Patrick’s-themed activities as well…
