Outdoors: STEM – explore changing states

What does it mean?

Changes of state refers to when matter changes physically, e.g. a solid changes into a liquid, or a liquid to a gas. Processes such as evaporation and boiling change the state of substances.

Quick win – freezing and melting

One morning, fill an ice cube tray with water and place it in the freezer. Go back to it every hour to examine – it usually takes around four hours for ice cubes to freeze. Once they are truly solid, remove them from the tray and place one or two on a series of five saucers. Test how quickly the ice cubes melt by pouring cold tap water on the first one, warm tap water on the next, boiling water on the third, and leaving the fourth and fifth to melt in the ambient temperature indoors and outdoors respectively. Ask children to predict what they think will happen at each stage, and why. You could repeat this experiment with much larger ‘ice cubes’ – freeze nesting hollow cups overnight. Estimate and then measure how much longer it takes the largest one to melt compared to the smallest.

Exploring STEM

For centuries, scientists and artists have told us that experimentation is just playfulness in another guise – including Einstein, who said ‘play is the highest form of research’. So I’m excited to be embarking on a new outdoor series, focusing on STEM – science, technology, engineering and maths. I’ll be adding that important ‘A’ for ‘arts’ in the middle too; as a landscape designer, I know just how interconnected creativity and technology are. In the early years, we have the advantage over our primary and secondary colleagues of being able to use our learning through play philosophy and positively embrace playful STEAM learning. Let’s jump in together!

In the moment – breathing

On a frosty morning, experiment with breath. Indoors, take a deep breath and breathe out – can children see anything? Try again, this time with a hand in front of their mouth – what can they feel on their palm? Is their breath warm, cool or cold?

Go outdoors and repeat the exercise. Children might note: their breath feels warmer outdoors than indoors (although it isn’t – it’s the ambient air temperature that makes it feel warmer); they can see their breath (because the gas condenses into water droplets in the cold air); and taking deep breaths feels more difficult outdoors (because the cold air makes our airways narrow).

Enhancement: subject to carrying out a risk-benefit assessment (see NW website for guidance), children can watch a small amount of water being evaporated to steam (a gas) in a metal spoon over a tea light candle. You can even condense it back again with a cold spoon held over the steam.

Continuous provision – mud lab

• Start the year by rethinking and rebadging your mud kitchen or digging area – from now on, let it be your setting’s Mud Lab.
• Start to change the language you use to describe the area and the play that happens in it, offering children STEM language to work with in the Mud Lab – lead discussions using words such as ‘compare’, ‘observe’, ‘investigate’, ‘test’, ‘properties’ and ‘evaluate’.
• Provide components and ingredients to generate chemical reactions – bicarbonate of soda is a fantastic ‘reactant’; make sure there is a ready supply of water available. I really love pelican pump buckets for this.
• Start to collect different kinds of vessels and implements – look for measuring jugs with scales on, turkey basters for drop-by-drop accurate mixing, plus clear plastic beakers and jars to allow children to observe the changes happening when they mix components together.
• Display images of doctors and scientists at work and provide face masks and goggles and children’s lab coats – there’s no better way to get STEM role play happening in the Mud Lab than to give children the real tools of the job.

Jan White and Liz Edwards’ Mud Kitchens booklet is a very handy guide (see Resources).

Enhancement – equipment:I’ve always advocated for young children having access to high-quality outdoor tools and equipment. Invest, if and when you can, in ‘real’ scientific equipment to explore changes of state. A set of Salter electronic scales is helpful and straightforward to use, and while they can’t be left outdoors, some of your children will really value their accuracy and hi-tech looks. A button resets them to zero, so children can keep adding to their potions.

A set of mechanical scales that can live outdoors is essential for your continuous provision, with the electronic scales offering much in the way of comparisons, discussions about the right tool for the job, why accuracy matters and so on. Consider sourcing a probe thermometer, which will enable children to measure the temperature of snow, soil, puddles – anything, really.

Book corner

The book Sneezy the Snowman is a fun story where the children attempt to ‘warm up’ a snowman who complains of feeling cold, with predictable but funny results each time.

Planning ahead

Slime and kinetic sand are both fascinating substances that children will enjoy creating and playing with – there are plenty of recipes and examples online, but the BBC Good Food website has recipes for both. This is an adult-led activity, so tackle making them like a scientific experiment, talking children through:

• The aim of the experiment: to create a substance we can play with, that is NOT a solid or a liquid, but is a polymer, with flowing, liquid qualities.
• The equipment and materials you’ll need: see the recipes online.
• The method you’ll use: talk about weighing, mixing, adding, kneading, rolling, resting.
• The hazards you might encounter: risk assessment; for example, will anything explode? Do we need to wear gloves?
• The outcome you expect: ask them about the texture, colour, smell and other qualities they think their version will have.
• Your observations as you carry out the experiment and create the substance.
• The final outcome: compare children’s expectations with the actual slime/kinetic sand they made. Are they pleased? What would they do differently next time?