Our Summer holidays are about to start, so I thought it would be a good time to spruce up this post full of Summer Science Challenges for kids. All the activities are very simple and use mostly things you probably already have around the house.
For an ultimate summer of science, try one activity each day, or just pick and choose the ones you like when you have a bit of spare time!
Why do a science challenge?
Science challenges are great as they give children the opportunity to work with more freedom than a traditional science experiment. Open-ended challenges can be great for teamwork and independent creative thinking. They're also great for a parent/child project, too!
FREE Printable Science Challenges
The lovely Mrs Mactivity has created some fun printable science challenges that you can cut out and use as prompts. Scroll to the bottom of the post to download.
If you haven't heard of Mrs Mactivity, do go and take a look at her website; she has some wonderful primary resources available.
Science Challenges for Summer
Build a tower with sugar cubes
A sugar cube tower is a fantastic, inexpensive STEM challenge. Children can build tall towers or bigger structures.
- How tall can you build a tower before it falls down?
- What happens if you spray the cubes with water?
- Can you add anything to stop water travelling up the columns of cubes?
Make your own lava lamp
All you need to make a lava lamp is oil, water and an Alka Seltzer or effervescent vitamin tablet. These are great as they can be used over and over again. Just wait for the reaction to stop, add a bit more Alka Seltzer, and it'll start all over again!
Make a treasure map
Use coffee or tea to colour paper and create a fun treasure map.
This is great for experimenting with different concentrations of liquid. A more concentrated tea or coffee solution will give a darker coloured map.
Invisible ink
Mix a little lemon or lime juice with water and write a message on a piece of paper.
Ask an adult to put it in the oven, and the message will appear.
What can you build with a cardboard box?
Can you build something functional with a cardboard box?
We added a kitchen roll holder and space for a sink to our cardboard kitchen.
Make a solar oven
Make a delicious dessert with a solar oven! This is a great activity for learning about reflecting and absorbing materials.
Simple sinking and floating
Design a sinking and floating experiment. This is a great paddling pool science activity on a warm summer day.
Children can make predictions first, then investigate to see if they're correct. Some items might surprise them!
Spinning Felt Tip Pens
Use cardboard discs to make spinning pens. You can make these with paper and thinner or thicker card to see which works best.
Coke and Mento Reaction
Drop a mento into a bottle of fizzy drink and watch what happens. Remember to stand back and drop the mento in as fast as you can!
As an extra challenge, kids can investigate whether low sugar drinks erupt better than full sugar varieties.
The coke and mento reaction is a science activity everyone should try at least once.
Investigate which substances react with baking soda
Can you predict which substances will react with baking soda? Were your predictions correct?
Go on a bug hunt
Looking for bugs is a fantastic summer science challenge that doesn't cost anything. Download my FREE bug hunt template to make it even easier!
Set up an easy egg drop experiment
Something like our Humpty Dumpty egg drop experiment always works well. The idea is to place an egg in a bag filled with a protective material and then drop the bag to investigate which material best protects the egg.
Blow up a balloon
Blow up a balloon with Alka Seltzer or an effervescent vitamin tablet. Alka Seltzer and water react together, releasing carbon dioxide gas. The gas fills the space in the container and then fills the balloon, inflating it!
Build a structure with marshmallows and straws
Warning - marshmallow and straw towers can be a bit sticky, but is great fun and a fantastic team building science activity.
Make a marble maze
Design and build a LEGO marble maze? Or use marbles inside a cardboard box.
Make a Baking Soda Volcano
The volcano below is made using papier mache, but sand also works well!
Check out our baking soda volcano ideas for inspiration.
Baking Soda Reactions
Set up some simple baking soda reactions outdoors. These could be fairy themed, witchy potions or just simple messy play.
Make Music
Play a tune using water and glass bottles. If you don't have glass bottles, make a guitar by stretching elastic bands over a cardboard box.
Square Bubbles
You can't really create a square bubble, but you can create something that looks like a square bubble using a cube frame dipped in bubble mix.
How strong is a Candy House
Build a house from sweets. We usually experiment with different types of "glue" to find out which works the best.
Once the house is built, the fun bit is testing how strong it is!
Ice Painting
Try some ice painting, simply freeze a sheet of ice or an ice shape and paint over the top. Once finished, you can wipe away your creation and start over.
Find the colours of the rainbow
Search for the colours of the rainbow in a bubble. When light from the sun shines through the bubbles, it is reflected and dispersed, splitting white light into its different wavelengths and revealing all the colours of the rainbow!
Split light with a prism
Can you split light into a rainbow using a prism?
Make ice cream with ice and salt
Use ice and salt to make ice cream from milk. This is a delicious activity for a sunny day. The salt lowers the freezing point of the ice, which then draws heat from the milk mixture, causing it to freeze.
Dissect a flower
Can you dissect a flower and separate the parts? Do you know the function of each?
Fairy Potions
Make a fairy potion, collect flowers and herbs to make a lovely smelling potion. Does the water change colour? Which smells are the strongest?
Jumping Frogs
Can you make some jumping frogs and learn about static electricity?
Sand Volcano
Make a volcano with sand. We covered this one with cling film to keep the sand clean.
Baking Soda Explosion
Can you make a fizzy baking soda explosion?
Build a raft
Can you build a raft with sticks and test to see if it floats?
Cork boats
Can you make a cork boat and test to see if it floats?
Rainbow in water
Can you spot a rainbow in a spray of water? This is an easy way to see light split into its constituent colours!
Spin art pictures
Use a salad spinner to make a spin art picture.
Slime time!
Create colourful slime using cornstarch, water, and food colouring.
Scrunch it to make it solid and then watch it run through your fingers as it turns into a liquid!
Football Box Game
Make a football in a box game by blowing down a straw to move marbles covered in paint. How many goals can you score?
Playdough Brain
Can you make a playdough brain? This is a fantastic way to learn about the various parts of the brain and their functions.
How to make an egg float
Try a bit of science magic and make an egg float. All you need for this simple science trick is an egg, jug, water and salt.
Why does Pizza Dough Rise?
Do you know why pizza dough rises ? Find out while making a delicious meal!
Even More Science Challenges
Make Raisins Dance
Make raisins dance around a glass with some clever science. Adding baking soda causes the raisins to move around, as if they're dancing!
Build a Giant Catapult
We used our giant catapult as a tennis ball launcher, but you could also try using water balloons or table tennis balls.
Science Challenge Cards
New for 2018 are these amazing Science Challenge printable cards, created for us by the wonderful Mrs Mactivity.
If these aren't quite what you're looking for, try one of my other fun science experiments for kids.
Last Updated on July 8, 2025 by Emma Vanstone
Kippi says
I love science these all look like so much fun I want to do some of them. Happy Summer, Kippi