What is Heat Transfer? Heat Transfer Experiments

Heat transfer projects are an exciting and engaging choice for your next STEM activity. Kids love the hands on nature of these projects. Plus they offer a lot of practical life skills. Like how to build a natural solar heater or how to slow heat loss, or how to make a slurpee with science!

Science Fair Heat Transfer Experiments

These Heat Transfer Projects For Kids provide lots of hands-on STEM activities to promote understanding of the laws of thermodynamics.

Heat Transfer Science and Definitions

Before jumping into a bunch of Heat Transfer Projects it’s a good idea to chat about the science behind these experiments.

Heat Energy is often called thermal energy. Thermal energy is present in the molecules of an object. When an object is hot the molecules have a lot of energy and move fast. When an object is cold, the molecules have little energy and move slowly.

One thing to keep in mind, is that the faster molecules are moving, the more space they take up. The Bottle Crush experiment below is a fantastic way to demonstrate this principle.

How is Heat Transferred?

The Second Law of Thermodynamics states that heat will always move from a hot object to a cooler one.  Heat transfer is the movement of thermal energy as it transfers from one object to another or between an object and it’s surroundings. Thermal energy will naturally work towards a state of balance or equilibrium. This is known as thermal equilibrium, where two objects or an object and it’s surroundings achieve the same level of heat energy (thermal energy).

Keep in mind the greater the difference in temperature the more rapid the transfer of heat. The Mpemba Effect is a great way to explore this principle in water.

What is the Difference Between Heat and Temperature?

It’s important not to confuse Heat and Temperature. Heat refers to the energy present in the molecules of an object (picture how fast those molecules are moving). Heat is affected by the speed of the particles, the number of particles (including their size or mass), and the type of particles. Temperature is a measure of the average kinetic energy of the molecules in an object and is not affected by the number or size of the molecules. Heat and temperature are directly related to each other, but not the same thing.

Picture a steaming mug of coffee, now picture a bathtub filled with the same steaming coffee. The temperature is the same, but the thermal energy is higher in the tub because there is more coffee.

In a nutshell, heat is energy. Temperature is a measurement of that energy.

So with these heat transfer projects we are exploring the transfer of energy, with temperature being a common method of measurement and quantification of the results.

Heat Transfer Projects and Experiments

Science Fair Worthy Projects

Greenhouse Effect Experiment – Climate Change in a Jar

In this climate change experiment students learn hands on about the power of greenhouse gases and how they capture and hold heat from the sun. A simple chemical reaction is all that is needed to replicate the carbon dioxide in the atmosphere and see the greenhouse effect in a jar.

Greenhouse Effect Science Experiment

Starlite Thermal Insulating Experiment

This project is absolutely fascinating and would make an amazing science fair project for middle grade. Our Starlite recipe uses ingredients that you probably already have and it provides incredible thermal protection from heat transfer. We tested it a number of different ways, and each was utterly fascinating!

Grade 7 science fair project idea using starlite for thermal insulation

Passive Solar Energy Project

This activity uses recycled materials to create a solar chimney. Using the energy from the sun, it is transferred to the air inside the chimney, heating the air.

Exploring Solar Heat - STEM Education. A fantastic idea for some outdoor STEM fun

Winter STEM – Exploring the Effect of Salt on Ice

A fun project that explores how salt impacts ice and the transfer of heat between the ice and adjacent objects and the surroundings.

A fascinating Winter STEM Activity for elementary kids exploring the effect of salt on ice. Significant results provide rewarding STEM hands-on learning.

Slurpee Science

Using the principles explored in the previous Winter STEM project, this heat transfer project has a tasty treat at the end as students make their own slurpees with science!

Sweet slurpee science is a fantastic activity for kids, with a tasty result they will love. This simple heat transfer experiment is perfect for all ages.

How to Make Ice Cream in a Bag

Want something other than a slurpee? Try making Ice Cream in a Bag using the principles of Heat Transfer and a little muscle power. We have recipes for regular and dairy free Ice Cream in a Bag. So yummy!

Ice Cream in a Bag Two Recipes including Dairy Free

Why Does Water Rise?

This activity is like magic and a great example of how rapid changes in heat energy and temperature can create a vacuum.

Why Does Water Rise? Best Science Experiments for Kids!

More Fun Heat Transfer Projects

Color Changing Magic Playdough Recipe

A wow worthy project making playdough that changes colour as you play, simply from the heat of your hands, or by using chilled or warmed objects. This Magic Playdough Recipe is so cool!

Magic Colour Changing Playdough

Heat Sensitive Color Changing Oobleck Recipe

Looking to add some non-Newtonian Fluid demonstrations to your heat transfer lessons? Try this fun Colour Changing Oobleck that changes colours from the warmth of your hands, especially as you work it to keep it in a solid state. But release it and watch as it turns to liquid, flowing from your hands and changes colour as it flows. A fantastic demonstration of heat transfer and non-Newtonian fluids.

On a teal and white striped background sits a white bowl filled with blue oobleck that has a purple handprint in the centre. Overlay text says Colour Changing Oobleck a Heat Transfer Experiment

Magic Moon Dough

This luxurious sensory activity is absolutely mesmerizing. As you play with the silky feeling magic moon dough it will change colour from your touch, just like magic! Takes only minutes to make and provides hours of play.

Magic Moon Dough that Changes Colour as you play

Bottle Crush

This activity was mentioned above. Bottle Crush is a very simple science project that kids of all ages will enjoy. It does a fantastic job of showing how high heat energy takes up more space and low heat energy takes up less space.

Bottle Crush - Crush a bottle with your mind, and a little science. Inspired by Mythbusters, a science experiment that seems like magic!

Mpemba Effect – Making Snow

The Mpemba Effect is about the peculiar property of water where it will freeze faster when it is hotter, rather than colder. The greater the difference in temperature, the faster the heat transfer and the more dramatic the results. And at -40 the results are breathtaking!

How to Make Snow and explore a cool property of water called the Mpemba Effect. It uses a little bit of science, a little bit of hot water, and a whole lot of cold to make this spectacular snow storm happen like magic.

Convection Currents Experiment

A potentially messy but fun experiment that shows how heat transfers between liquids when they are mixed together.

Ocean Currents Experiment

Similar to the experiment above, this one also explores heat transfer in liquids and how liquids at extreme temperature differences react to each other.



Heat transfer projects and science experiments