5 at-home science experiments that are perfect for a storm day

Stuck at home today? Mark Langtry, aka ‘The Science Guy’ shows us how to make slime, a lava lamp and a blob monster
5 at-home science experiments that are perfect for a storm day

Mark Langtry is passionate about science and making it accessible for all from a young age. The Director of Sports and Science at Explorium in Dublin, he is at the forefront of their mission to make science, technology, engineering and maths (STEM) fun and accessible for children and he hasn’t let a global pandemic stop him.

 Mark Langtry head of science and sport at Explorium
Mark Langtry head of science and sport at Explorium

A former Shamrock Rovers footballer, he finds blending science with things kids are interested in is a great way to keep their attention.

“It’s not only that you understand how the world works, but if you’re a footballer, you understand how to kick a football to make it do certain things. Kids really relate to stuff like that, things that they like, things that are relevant in their lives,” Mark says.

“I played professional football for 10 years so I understood how important science is in a player’s performance. Footballers track their data using sports trackers so they can see how fast they can run, how high they can jump and they can see if their training is working. If not, they can change it and they can get faster. 

"All the best athletes in the world are using science to help them improve. If you can teach a kid some piece of information that helps them run faster or jump higher or make a better decision, they love that kind of stuff.”

5 science activities to try at home:

Frankenstein's Balloons 

What you’ll need:

  • Plastic bottle 
  • Balloon 
  • Vinegar 
  • Baking soda 
  • Funnel or piece of paper 
  • Food dye (optional) 

What you’ll do:

Draw a scary face on the balloon before you blow it up 

Pour vinegar into your bottle (100ml) 

Add some food colouring.

Then, using a funnel (or a rolled-up piece of paper) fill your balloon about half full with baking soda.

Attach your balloon to the top of the bottle (making sure no baking soda falls in yet).

When you're ready, lift the balloon, the baking soda drops into the vinegar, and your balloon will start to expand 

What’s going on? 

The baking soda (a base) and the vinegar (an acid) react together and create carbon dioxide gas (and salt and water). This CO2 gas expands and increases the pressure inside the bottle, and causes the balloon to inflate! 

The more CO2 that is released, the bigger the balloon gets, and the bigger and scarier your drawing gets as the rubber gets stretched apart!

'Oobleck' the Blob Monster  

With some very simple ingredients you can create your very own blob monster and explore the weird world of Non-Newtonian Fluids 

What you’ll need:

  • Warm Water 
  • Cornflour 
  • Mixing bowl  
  • Food dye (optional) 

What you’ll do:

Mix approx 1 part water (coloured with food dye if you wish) with 2 parts cornflour in your mixing bowl.

Use your hands to mix it about until it forms a nice gloopy fluid. Then the fun begins! Experiment tapping, pressing and hitting the mixture and see what happens!!!

What’s going on? 

Most things either act like a solid, liquid or a gas. Not Oobleck. A little bit of pressure changes everything. 

Applying a force to the liquid Oobleck causes the floating bits of cornflour to suddenly clump together and it acts like a solid. Move slowly through it, and it remains a liquid. Try rolling it in a ball in your hands, or slapping it to see if it splashes.

Make sure to throw your Oobleck in the bin when you are finished playing with it. Not down the sink, where it can clog it up... that’s the last thing you want after a day of fun! 

DIY Lava Lamp 

What you’ll need:

  • Bottle or Jar 
  • Water 
  • Sunflower Oil (or vegetable oil) 
  • Fizzy Tablets 
  • Food colouring (optional) 

What you’ll do:

Pour some water into the bottle (up to about 2 inches is fine).

Carefully pour the sunflower oil in the bottle, filling it almost to the top.

Add some drops of food colouring in, and watch as they fall through the oil and settle on top of the water.

Drop about half a fizzy tablet into the bottle, and watch your lava lamp come to life. You can add more fizzy tablets to keep it going!

What’s going on? 

Oil and water have different densities, so they do not mix. The oil is less dense (or lighter) than water, so it floats on top. When you add the fizzy tablet, it falls down into the water and a chemical reaction occurs, releasing a carbon dioxide gas (CO2). 

These gas bubbles are lighter than the water, and oil, so rise to the top (carrying some of the food colouring with it) and escape out the bottle. The food colouring that just hitched a ride with some CO2, falls all the way back down to the bottom of the bottle! 

This process repeats over and over until the CO2 runs out!

It's Slime Time 

How to make slime at home. 
How to make slime at home. 

What you’ll need:

  • PVA glue 
  • Baking Soda 
  • Contact lens solution (one that contains boric acid) 
  • Mixing Bowl and teaspoon 
  • Food colouring (optional)


What you’ll do:

Pour some PVA glue into the bowl (1/2 cup) 

Add some food colouring and if you’re feeling crazy try some glitter.

Add a teaspoon of baking soda.

Then add approx 1 teaspoon of contact lens solution and mix it all together. Now squeeze, stretch and play with your super slime!

What’s going on? 

Glue is made of long chains of molecules called polymers. Contact lens solution contains boric acid which helps bind the glue molecules together. 

The bread soda releases the borate ions from the contact lens solution and they get to work, cross linking and hooking those long chains of molecules together to form slime!

Rainbow Explosion 

What you’ll need:

  • Milk (full fat) 
  • A plate 
  • Food colouring  
  • Washing up liquid 
  • Cotton bud 

What you’ll do:

Pour some milk onto the plate 

Drop some blobs of food colouring into the milk.

Put a drop of liquid soap onto a cotton bud (You can also just use your finger) 

Dip the cotton bud (or your finger) into the colours in the milk and watch the swirling explosion of colour!

What’s going on? 

This milk colour explosion is all thanks to surface tension and the bonding of molecules When we dip the soap in the milk, it breaks the surface tension layer, which is like a very thin 'skin' on the surface of the milk. 

It also starts connecting with fat molecules in the milk. We can see all of this movement thanks to our food colouring getting pushed out of the way, as the soap searches for more free fat molecules in this beautiful swirling rainbow.

More in this section


The best food, health, entertainment and lifestyle content from the Irish Examiner, direct to your inbox.

Sign up