10 Exciting Free STEM Activities for 3rd Graders

Are you looking for some fun STEM activities for 3rd graders? You’ve come to the right place!

Third grade is a super important year for a kid’s school life. When you look into 3rd grade, you’ll see that this is the year kids move from just learning how to read to using reading to understand more things. During this time, your child is probably getting better at schoolwork, growing physically, and fitting in with friends.

By implementing STEM education in your child’s teaching, you will allow your child to observe the world around them. The more they get to observe, the more they will learn. 

Everything our children do is an experiment for them. They are making discoveries and piecing together everything they see to understand the world they live in. When you let your kids play and experiment you will notice so many STEM concepts taking place.

STEM education is the combined approach to learning and teaching of the subjects Science, Technology, Engineering, and Mathematics. Instead of teaching these as separate subjects, STEM education blends them into an interconnected learning model based on real-world applications with hands-on learning. It emphasizes problem-solving, critical thinking, and creativity preparing your child for the challenges of the 21st century.

In the guide below, we’re going to share 10 of our favorite STEM activities for 3rd graders that your kids and students are sure to love!

Why Should You Include 3rd Grade STEM Activities in Your Lesson Plans?

The benefits of STEM education are something every parent should think about for their child’s future.

First, in today’s tech-filled world, STEM skills are really important. When kids learn STEM, they get better at solving problems and understanding a world full of technology.

STEM helps kids think deeply and to be curious. Instead of just believing everything they hear, kids learn to ask questions and try things out. This doesn’t just help with Science and Math; it will help them make good choices every day. STEM makes kids creative. For example, in engineering, kids think of new ways to fix problems. This means kids can do more than just use things, they can make new things!

Job opportunities in STEM are growing fast and these careers pay well. Children who learn STEM will have a better chance at a good career going forward. 

STEM also teaches kids to keep trying. When they test ideas, sometimes it won’t work. But they learn that it is okay, and they should just try again.

So, for parents who want the best for their kids in today’s world, choosing STEM education is a great idea. 

Doing STEM activities with your kids provides quality time for you to bond, it is fun, and children will love the learning experience which in turn will make of them lifelong learners.

10 Fun STEM Activities For 3rd Graders

Here are some incredibly fun 3rd Grade STEM activities kids are sure to love…

1. Bug Identification Activity

Children naturally possess a curiosity for bugs. While some kids are fascinated and eager to catch them, others remain equally intrigued but become hesitant when you attempt to bring them closer. Nonetheless, it’s important to recognize that their fascination continues, although each child’s reaction may be different.

This is an engaging STEM activity for third graders that guarantees a break from screens and encourages your child to spend time outdoors looking for and investigating all the bugs in your backyard. Learning truly is empowering, and that extends to understanding bugs as well. By being outside, your child gains a deeper appreciation for nature, observing the connected relationships that unfold within it.

Get the full project:  Bug Identification with Kids

2. Ocean Zones in a Jar

We dream in colors borrowed from the sea capturing the perfect balance between light and dark that is hidden in its layers.  When I look at the ocean and I feel inspired, my imagination runs freely, and my heart is filled with joy. 

Yet, its enormity and complexity also remind me of our insignificance, considering the thousands of sea creatures that call it home. This captivating STEM activity merges two scientific investigations.

It first introduces the principle of liquid density and secondly, it explores the topic of ocean zones.  Of course, there are plenty of relevant topics that can also be included providing limitless opportunities for ongoing discussion and discovery.

This activity is versatile, accommodating various age groups. A 3rd Grader is ready to understand advanced concepts such as density and layer formation. Demonstrating greater independence, your child can navigate through the experimental steps with little guidance, highlighting their growing scientific skills.

Get the full project: Ocean Zones in a Jar

3. Toothpick Bridge

“Today is the opportunity to build the tomorrow you want.” This thoughtful statement echoes deeply when considering the activities of our young children. They are given tasks like building structures, not just as simple assignments, but as foundational experiences. Each brick they lay, each design decision they make, is a step towards shaping their future. It’s not just about the physical structure they create, but the development of skills, understanding, and confidence that will serve them in the tomorrows to come.

Your 3rd Grader will be able to apply Physics, Maths, and Engineering skills to complete the structure. You will be nothing but proud of how their skill set has developed when this activity is being repeated from a previous time.

Get the full project: Toothpick Bridge STEM activity

4. Dragon Fire Science Experiment

“Be warned.  I’m bored.  This could get dangerous.”

The perfect bedroom slogan for parents with little exploring scientists wandering around the house.  Although this STEM experiment may potentially be dangerous for your 3rd grader, we recommend it be done under strict adult supervision. But that being said, this experiment is dangerously cool and highly educational.

So, two words to get your child excited:  Fire and Dragons!  What is not to love?  In this experiment, children will learn that the chemical elements in the flame can also alter the colors of the flame.  Children use different materials to see what happens (what color the fire turns) when a specific material is put into the fire.  This activity is pretty to observe and guarantees to be more fun than television and their phones.

Get the full project: Dragon Fire Science Experiment

5. Homemade Edible Pop Rocks

They say you are what you eat.  So why not make it something sweet?

This homemade edible STEM activity absolutely rocks.  It is colorful, beautiful, and full of learning.  Teach your children how crystals form in nature with this taste-safety food science experiment.

Growing crystals offers a delightful way to explore solutions, molecular bonds, patterns, and energy.  All of these happen by using only two simple ingredients: sugar and water. Sounds fun and easy!

Get the full project: Homemade Pop Rocks Experiments

6. DIY Composting STEM Project

I’d like to introduce you to a spectacular rubbish heap (also known as a compost system) for your garden.  Name your new compost bin to make it more fun for your child and play games to see how many things e.g. a handful of leaves, fruit and vegetable peels, or freshly cut grass they can gather daily in the garden and then…Wait for spectacular end results (over time) when you keep feeding the bin. 

Help your 3rd Grader to understand the three R’s (Reduce, Recycle, and Reuse) and how to implement these using composting effectively.  This process will minimize waste and contribute positively to the planet.

Additionally, your child will gain a deeper understanding of the importance of insects, worms, and microorganisms and recognize their invaluable role in our ecosystem.

Get the full project: DIY Composting STEM Project

7. Make Your Own Fun Invisible Ink

The world seems miraculous when children believe in magic.  While children still develop their cognitive skills and try to understand the world around them it is in their nature to think of Science as magical with their childlike imagination.

Teach your 3rd Grader about Oxidation and how it can be used to make invisible ink.  They will have a blast writing secret notes to friends or family members and have them decode the message using the revealing technique (often applying heat or a special light).  Maybe your child prefers to make magic drawings, do a secret diary entry, or hold a treasure hunt revealing clues at each step, the possibilities are endless.

Get the full project: How to Make Invisible Ink

8. Tin Can Ice Cream Science Experiment

I scream. You scream. We all scream for ice cream. Right?

So I think one of the things most mums have in common is that we all love our kids, we all love to eat, and I am sure we all love ice cream.  The best experiments are the ones that have either a product that we can use, regift or get to eat.  This is the ‘eat’ type of experiment that is fun and tasty.

Your 3rd grader and the rest of the family will absolutely enjoy this yummy experiment.  It will help teach students how simple physics works, and how work and force can change matter into something else. It might also teach them a little about patience and work ethic as they churn, shake, and create their own ingredients to make their own lovely ice cream. All you need is heavy whipping cream, sugar, a pinch of salt, some flavoring, and of course a tin can.

Get the full project: Tin Can Ice Cream Science Experiment

9. Hurricane STEM Challenge

A 3rd Grader might know that hurricanes come from the ocean and that they can cause damage. At this age, they might also be more curious about why hurricanes happen and how they form. Mostly their understanding might be mixed with misconceptions or imaginative elements thus is it the perfect time to introduce your child to this STEM challenge where they will learn about hurricanes and try to build their own hurricane-proof house.

I always feel that the more I know of something and understand it, the more empowered I feel especially when it comes to something like natural disasters.

By completing this activity your child will not only have a greater understanding of hurricanes, but they will also be better equipped with essential information about safety.  This knowledge and understanding will promote your child’s cognitive and emotional development.

Get the full project: Hurricane STEM Challenge

10. STEM Bottle Rocket Experiment

Dream big little one.  Shoot for the moon and even if you miss you will end up with the stars.  This is how we should encourage our little explorers.  They should always try, no matter the outcome, as long as they try, learn, and try some more they will eventually with hard work land on the moon.

A bottle rocket is a fun and easy experiment that works using a simple science trick! When you mix baking soda and vinegar inside a bottle, they create a gas called carbon dioxide. The gas that builds up tries to escape, and the only way out is down through the bottle’s nozzle. This forceful push of gas downwards makes the bottle rocket shoot up into the sky! It’s like when you blow up a balloon and let it go without tying it – the air rushes out, and the balloon zooms away!

Get the full project: The Bottle Rocket Experiment

Want More STEM Project Ideas Delivered Right to Your Inbox?

For more exciting experiments and fascinating STEM activities kids in all grades can enjoy and learn from, make sure to check out our STEM Made Easy Digital Subscription. Every month, you’ll get an email with a brand new, exciting collection of curated hands-on STEM project blueprints along with some accompanying resources and worksheets, helping you create fun-filled learning tasks in no time at all.

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More STEM Resources to Check Out

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