This is the CHaOS demonstrator website, mainly intended for our student volunteers. Click here if you were looking for our main front page.

CHaOS Experiments

Experiments sorted by name (ascending)

The page below lists all the CHaOS experiments currently in use. Use the selection box to filter experiments by subject area. Note that there is significant overlap between subject areas - many engineering experiments could easily be classified as physics, medical experiments as biology etc.

Please note a slightly more complete list of experiments exists here

Sort by name (descending)

Air Rockets

Launching lemonade bottle air rockets along a rope

5, 4, 3, 2, 1, Lift Off! With a lemonade bottle and a bike pump, we'll show you how to make a rocket! How high can you get it to fly?

Air Streams

Balancing balls on upward streams of air, and looking at aerodynamics.

Can you make something float on thin air? Find out how to levitate ping pong balls and why planes can fly in this entertaining experiment.

Air Streams (Plus)

Newton's laws, stable equilibria, drag, lift, Magnus Effect

How can you make things float and fly on air alone?
Explore the physics of floating, lift and stability!


Materials Science

Animal Cognition

A challenge to get people thinking about animal intelligence

Intelligence tests for animals.

Animal skulls (including primate skulls)

Looking at different animal skulls to compare them and see how they differ.

Why do some animals have really long beaks? Why do others have really big TEETH? With our collection of animal skulls, you can find out how different animals evolved to suit their habitats - and how you are a lot more similar to them than you might think!

Arch Bridge

Building an arch bridge, and then walking over it.

Can you build a bridge strong enough to walk on?

Articulated Knee Model

A spare plastic skeleton leg, now with added ligaments.

Come and see the complexity behind how your knee works!

Blind spot test

A simple test to show that there is a blind spot on the retina of the eye

Did you know that everyone has a blind spot in their eyes? Never noticed before? Use our blind spot test to find yours!

Blood Glucose

Learn about diabetes and try using a handheld blood glucose meter.

Blood Groups

Why are blood groups important?

Why is it important to match blood groups for transfusion? Find out with our colourful demonstration.

Bouncing Balls and Falling Toast

Looking at odd properties of bodies with spin.

A selection of mechanics experiments which investigate the properties of bodies with added spin. From bouncing balls of walls to dropping toast from tables we find out the hidden influence of angular momentum and why it makes our carpet buttery.

Brain Model

Anatomical model of the brain.

Have you ever wondered what the brain looks like? Come and discover the structure of the brain and the different functions each part has!

Bubble Guns


Magical bubbles

Build a Tree

Talk about the different parts of a tree whilst building one out of craft materials

Camera obscura and lenses

Peering at the outside world through a lens.

The camera obscura uses a lens to project an image of the outside world onto a white screen inside the CHaOS event. Can you figure out why it's upside down?

Cantilever Bridges

Building a series of cantilever bridges

Can you build bridges across wider and wider rivers?

Carbon Allotropes and Molecular models

Explore some elements and different types of bond and explore ways carbon can bond to form different allotropes.


How can we use arches to hold up a cathedral?

See how simple shapes can fit together to hold up a large structure, like a cathedral!

CBS Robotics Workshop

Robotics Workshop run during CBS, in conjunction with Robogals Cambridge
Please note: This experiment is not used on the summer roadshow

Chromatin Pipecleaner Models

Explore the world of epigenetics, using pipecleaners and corks to model DNA and the chemical changes done to it to turn genes on and off.

Humans have 19,000 genes. How are only certain genes turned on in each cell so that brain cells express brain genes, but not heart genes and vice versa? Here we make fun chromatin models to explore epigenetics.

Cleaning Coppers

Removing copper oxides from coins.

Those grubby coppers in your pocket or purse can be shined up in minutes, give it a try and find out how it works.

Please note: This experiment is not used on the summer roadshow

Colour mixing

Dimmable, focussed red, green and blue lamps for experimenting with light colour mixing

How many colours can you make? With our coloured lights, find out how you can make every colour imaginable from just three colours, find out how your computer monitor works and get to see some really funky shadows!


Explore the remarkable properties of cornflour mixed with water.

Slimey, gooey and messy: cornflour is one of our favourite experiments! Come and stick your hands in, and figure out if it behaves like a liquid or a solid...

Creepy Crawlies

Looking at a variety of small creatures that you can find in your garden

Insects, worms, bugs and more: what lives in your garden? Get up close and personal and see for yourself!

Please note: This experiment is not used on the summer roadshow

Dissecting sheep's eyeballs

Dissecting a sheep's eyeball to show the structure of the eye

Only at "Crash, Bang, Squelch!": see the inner workings of the eye first-hand by dissecting a sheep's eyeball! Feel the smoothness of the lens, prod the gelatinous fluid and see the amazing coloured sheen of the layers that help sheep see better in the dark.

Please note: This experiment is not used on the summer roadshow


This experiment aims to introduce kids to a wonderful model organism, the Drosophila fruit fly.

You'll have seen some of these fruit flies before: these cool and beautiful little creatures have shown us how genes can be inherited (by following patterns of features like eye colours), and how genes work.

Please note: This experiment is not used on the summer roadshow

Ear model

Anatomical model of the ear, with removable parts.

Use our large-scale model of the ear to discover how it enables you to hear sounds.

Ear switching hat

This magical hat will confuse your senses!

Sound cues can help us figure out where things are located in the environment - try confusing your brain with the Ear-Switching Hat!

Epidemiology CHaOS plus!

Show kids how disease dynamics, with a model of Citrus Canker spreading through a population of orange trees

Exploring the concept of disease spread and biological modelling.

Evolution Games (PLUS)

Modelling Evolution by Game Theory

Simulate populations and explore stable and unstable equilibrium by using Game Theory to model animal behaviour in sharing a food supply.

Exercise and Heart rate

When you exercise your heart beats faster!

Why does your heat beat faster after exercise? Come and find out why in this demonstration where you are the subject.

Eye Model

Anatomical model of an eye with removable parts to show the structures inside.

Use our amazing model of a human eye to see the intricate structures which allow us to see the world.

Fire Extinguishers

Demonstrating the power of a carbon dioxide fire extinguisher.

What does a fire need to burn, and how can we put it out? Find out how we can put out a candle with a cupful of gas!

Giant Bubbles

Making giant soap bubbles and looking at how they behave in different shaped frames.

I'm forever blowing bubbles... but why aren't any of them square? Can you make a square bubble? Come and have a go...

Please note: This experiment is not used on the summer roadshow

Giant intestine model

Functional model of the intestine

Everyone knows that your intestines are long, but how long is long? Find out with our scale fabric model, and you might be surprised!

Graph Theory

Find out about the mathematics of Graphs.

Experiment with graphs finding out about what structure we can find in randomness, how to colour maps with few crayons and what shapes you can draw without taking your pen of the paper.

Hand Model

Large working model of a hand and forearm, with all the tendons to show how a hand works.

Take control of an enormous hand, playing the part of the muscles that control it! Can you work out how to make a fist? Why are there tendons running down both sides of the fingers? And exactly how are your thumbs different to your fingers?

Handy Engineering

Build a small working model hand from card and straws!

Build a model of the inner workings of your hand! Learn about how muscles and tendons work together to control the movements of our fingers, and have a model to take home, made of simple household objects!

Heart Model

Anatomical model of the heart to show how the heart works.

An anatomical model of the heart providing an opportunity to talk about the the circulatory system and find out why we need blood.



Turning a hexaflexagon inside out almost seems like magic. Find out what kind of cool patterns emerge as you do it.

Horse Racing

Probabilities of rolling dice.

Understanding the probabilities behind throwing pairs of dice.

Hot Air Balloons

Making hot air balloons with plastic bags and a toaster.

Make your own hot air balloon with a plastic bag and a toaster!

Jaw model and giant teeth

Anatomical model of the half jaw, parts can be removed to show structure of the teeth.

An enlarged model of the jaw with some giant teeth that can be opened up. Find out why we have milk teeth, why there are different types of teeth and why different species have different teeth.

Kiwi DNA

Breaking open cells of a kiwi fruit and making the DNA inside visible to the human eye

In this experiment we get DNA out of living cells in kiwi fruit. The DNA can be made fully visible to the human eye - no microscopes or magnifying glass needed! Done in less than 5 minutes in front of your eyes.

Kruskal's count

Players follow playing cards around a circle and watch as they magically come together

Players follow playing cards around a circle and watch as they magically come together

Larynx model

Functional model of the larynx

A working model of the larynx which uses a hand pump to force air across two closely-apposed rubber sheets (i.e. vocal cords) to make a sound.

Lenz's Law

What happens when we drop a magnet through a pipe?

What happens when we drop a magnet through a pipe? Experiment with dropping them through perspex and metal pipes and see if there's any differences.

Locusts and Glowsticks

Using glow sticks to talk about chemical kinetics.

What do glowsticks and locusts have in common? Watch what happens as we heat them up and cool them down - how long can you get your glowstick to glow? How fast can you make the locusts move?

Please note: This experiment is not used on the summer roadshow

Lung Model

Working model of the lungs with diaphragm and rib cage.

Use our interactive model to find out how we breathe.

Mechanical advantage

Using pulleys and levers to explore mechanical advantage

Check out this huge tripod with weights and pulleys, then try using pulleys and levers to explore the idea of "mechanical advantage"

Microbes: bacteria

Cuddly bugs, props from a lab, and a hand-washing experiment

Bacteria are living things made from only one cell. You've probably heard about how they cause disease, but you might not know about some of the friendlier ones that are useful to us. Come and investigate our extra large cuddly microbe collection!

Microbes: parasites

Get up close an personal to some parasites (well, preserved slides), and find out more about them...

Parasites are a massive problem for global health, particularly in the developing world. Find out more about these creatures, who get a bit too close for comfort!

Microbes: viruses

Cuddly viruses and a few models too

Viruses are tiny particles that infect animals and plants - causing infections like chicken pox. Come and have a look at our cuddly viruses and hear more about what they do!

Microscopes & Cells

Examining a variety of objects under a microscope, including a variety of slides

All sorts of things can be viewed down a microscope! This might include the biology lesson classic of an onion skin, the shapes of salt and sugar crystals, the eye of the insect you found in your tent, a drop of puddle water...

Mini Explosions

Exploding film canisters with lemon juice and bicarb.

Make an impressive explosion with kitchen ingredients and find out more about what makes things go with a bang.


A variety of sea life and freshwater animals observed using microscopes
Please note: This experiment is not used on the summer roadshow

Model cells

Box of model cells

You'll often see these model cells helping to explain other biology experiments, but one day they may get their own solo careers...

Mould Effect (Self-Siphoning Beads)

Letting a chain pull itself out of a beaker under its own gravity

Why on earth do the beads have to go up to come down?! Watch them fly out of a beaker, looping and corkscrewing, and find out about the amazing Mould Effect!

Near IR webcam

Use a modified webcam to see into the near infrared.

There's a whole spectra of light beyond the visible, why not see one side of it through a modified webcam?

Non-Transitive Games

What's the best option in games of chance?

Some games really aren't fair. Even if your opponent knows your exact move you can still beat them. Explore some of these games and find out there might not be a sensible best choice.

Organ Vest

A velcro apron with detachable 3D organs, to show what's inside your body.

See if you can correctly place body organs using this wearable felt and velcro vest.

Peak flow

Using a peak flow meter to measure peak flow rates

A peak flow meter often used by medical staff to measure the maximum speed you can expel a 'huff' of air.

Please note: This experiment is not used on the summer roadshow

Phase Game

Game introducing the phases of matter and phase changes

Outside game introducing the concept of different phases of matter and the different ways to transition between them.

Pipe-cleaner neurones

Making model neurones from coloured pipe cleaners!

Neurones are cells in your brain, that connect to lots of other neurones. Make some brains cells yourself with brightly coloured pipecleaners and the expert help of one of our demonstrators.

Plant evolution & pollinator game

Plant evolution timeline and matching plants with their pollinators


Plants - looking at germination, their structure and how they produce energy by photosynthesis
Please note: This experiment is not used on the summer roadshow


Discover how polaroid filters block light as you turn them round

Experiment with the properties of light as certain filters block light, but only in certain directions!

Polarisation PLUS

Discover how polaroid filters block light as you turn them round

Pond Life

A selection of organisms from a local pond or rock pool
Please note: This experiment is not used on the summer roadshow

Prism Goggles

Demonstrate how the brain adapts to changes in environmental input using prism goggles.

See how quickly your brain adapts by wearing our prism goggles whilst playing a target-hitting game.

Psychedelic Milk

See the amazing patterns made by food colouring and detergent in milk.

A little milk, a little food dye, a little washing-up liquid... and an amazing display of colour. See the stunning swirling effects from disrupting the surface tension.

Random Walks

Choosing direction using a coin flip.

See how biased coins and random chance can lead to surprising conclusions.

Red cabbage

Making a natural pH indicator.

We use a little red cabbage juice to find out more about acids and bases in the world around us.

Renewable Energy: Uses of Electromagnetism

Making power using wind and water!

Explore how we can use the power of electromagnetism to power our day to day lives!


What is the link between earthquakes and cello strings?

Reversible Flow

Turn syrup one way, then the other, and see that it gets back where it started.
Please note: This experiment is not used on the summer roadshow

Robots on tour!

Challenges that can be done with robots in a relativley short time period.

Learn to programme LEGO Mindstorms and learn about IF statements and LOOPs.

Rocks and Fossils

A box of rocks and fossils

Find out about explosive volcanoes, shiny crystals, and the exotic animals that lived millions of years ago.

Rod Climbing

A polyacrylamide solution, which "climbs up" a rod when it is rotated in the solution

Discover a strange goo with same strange properties. Watch as it is able to climb up a rod in front of your eyes!

Rolling Down Hills

Racing jam jars down a gentle slope, to see how filling them affects the speed.

Test out moments using jam jars of differing weights in a race downhill.

Scale of the Solar System

By comparing sizes and distances we can scale our solar system all the way up from the Earth and the Moon, up to our nearest star, and you might be surprised how far that actually is!

By comparing sizes and distances we can scale our solar system all the way up from the Earth and the Moon, up to our nearest star, and you might be surprised how far that actually is!

Seeing Sound

Use an oscilloscope and slinky spring to see how sound travels

Find out what sound is, the difference between low and high sounds, and loud and quiet sounds, and learn about sounds we can't hear

Skeleton and bones

Meet Boris, the friendly CHaOS skeleton.

Boris is a friendly life-sized plastic skeleton- come and say hello!

Slug Bubbles

Does a tube of water drain more slowly with a bung in the top?

Does the diameter effect how fast water drains from a sealed tube? Watch the bubbles produced and see which is fastest.

Sodium Acetate

Rapid crystal growth from sodium acetate.

Find out about how handwarmers work, and see solid crystals form in seconds right in front of your eyes.

Please note: This experiment is not used on the summer roadshow

Sounds from an oven shelf

Get very strange sounds from an oven shelf.

Spaghetti Loading

Materials Science

This experiment uses uncooked spaghetti to explore elastic buckling of vertical columns and 3-point bending of horizontal beams.

Spinning Chair

Use a freely spinning chair, some masses and a bicycle wheel to see some unintuitive physics.

Spinning Eggs

How to test if an egg is uncooked or hard boiled.


Using a stethoscope to listen to the heart and find out how it works.

A chance to listen to your heartbeat, and to find out why your heart beats faster and slower sometimes.

Sunset Model

Why is the sky blue and the sunset red?

Have you ever wondered what makes the sky blue? Or why it stops being blue at sunset? Come along to this experiment to find out why!

Surface Tension

Exploring surface tension through floating paperclips and racing boats

Suspension Bridge

A suspension bridge made from rope and wood that children can walk across.

Walk across our bridge, then find out what makes it stay up.

Please note: This experiment is not used at Crash Bang Squelch!

Sweet Chromatography

Using chromatography to investigate the colour of food.

Using just water and bits of paper, split up the colours in pens and food colourings to see how they're made up of a mixture of differently coloured dyes.

Please note: This experiment is not used on the summer roadshow

Tendon Hammer

Using a tendon hammer to show and explain some strange reflexes

Have a go at using a tendon hammer to show and explain some strange reflexes...

The Mathematical Bridge

How can a bridge stay up without bolts?

Self supporting bridges using only wooden poles.

Thixotropic sand and fluidised bed

Looking at floating and sinking using a bed of sand

Find out more about quicksand and how sand can behave like a fluid.


Using a medieval inspired siege-weapon to launch bean bag bunnies

Fire bean-bag bunnies across the room using our trebuchets! Can you work out how to make them go really far?

Turtle Robots

These turtles want to draw you shapes.
Computer Science

Learn the basics of robotics by teaching simple robots to move and draw.


Practise diagnosing patients using this simple bedside test - use the dipsticks to analyse "urine" from our patients.

Use of active expression handsets

Please note: This experiment is not used on the summer roadshow

UV (Fluorescence)

Looking at how materials fluoresce in UV light.

The world looks different when it's lit by UV... see how you can use this type of light to make clothes look extra-bright, find out whether banknotes are real or fake, and revive dead glowsticks.

Vacuum Bazooka

Firing a projectile using a vacuum cleaner and a long tube.

Experiment with launching projectiles using the power of a vacuum cleaner.

Vegetable oil and pyrex

Using the refractive index of vegetable oil to make a glass bowl 'disappear'.

Ordinary glass objects seem to disappear as you submerge them in a bath of oil. This experiment is spectacular and very messy!

Water Fibre Optics

Constraining light in a stream of water, making it work like an optical fibre.

Find out what happens when light is trapped inside a stream of water. Make a beam of light bend round corners and see how fibre optics are helping to change the world!

Water rockets

Launching lemonade bottle water rockets with a foot pump.

Try not to get wet as you fire water-powered rockets into the air. Who can shoot it the highest?

X Rays

A collection of x-rays and other forms of medical diagnostic imagery.

Have you ever had an x-ray? Have you ever wondered how they work? Take a look at our collection of exciting x-rays and MRI scans, test your anatomical knowledge and diagnostic skills and find out about the physics behind the images.


Showing one of the transport systems in plants.

Combine food colouring with water transport in stem and flowers- you can then see where all the water goes!

Please note: This experiment is not used on the summer roadshow

Yeast & bread making

The idea is to look at how yeast grows and how it relates to bread making. It involves getting the kids to make bread dough.

Like all the best biology experiments, this is hands-on and messy! See what happens when you add living yeast to a bread mix, and don't forget to come back a bit later to see what's happened to your dough!