50 science experiments for your kids to try

This is a great way for the kids to learn new things while having oodles of fun. We've got all bases of science and abilities covered in these 50 science experiments ... give them a go, you might even learn something yourself!

School-age kids should be able to grasp this one, but it may be too tricky for little ones to understand. The idea in this experiment is to see how the density of water affects buoyancy.

What you need: three tall, clear glasses (identical ones are best); three eggs; a tablespoon; something to stir the water gently (e.g. a straw); water; salt.

What to do:

1. Fill up each glass halfway with water. Put one egg in each glass. Choose one of the glasses to be the control glass (glass 1) – that means you won't do anything to it.

2. Add three tablespoons of salt to one of the non-control glasses (glass 2). Gently mix it in the water.

3. Add 10 tablespoons of salt to the other non-control glass (glass 3) and gently stir it. Slowly pour water into the glass until it's full, but don't stir it, so that you keep as much of the salty water at the bottom as you can.

The explanation:

Glass 1: This glass is a fresh water environment, so the egg will sink to the bottom.

Glass 2: This glass is a salt water environment, so the egg should rise to the top and float.

Glass 3: This glass shows what happens when you add fresh water to salty water, so the egg should be suspended in the middle.

Salt makes water more dense and the more dense a liquid is, the greater its buoyancy, which means it's easier to float. When you add fresh water to the more dense salt water, it will also float. You can tell exactly where the salt water and fresh water meet in the glass by where the egg is floating.

Who doesn't love a lava lamp? This experiment is a fun way for kids to understand density.

What you need: a clean plastic bottle (try to use one with smooth sides); water; vegetable oil or baby oil; fizzing tablets, such as Alka Seltzer; food colouring.

What to do:

1. Fill up one quarter of the bottle with water.

2. Pour the vegetable oil into the bottle until it's almost full. You might want to use a measuring cup with a spout to avoid mess. Wait a couple of minutes for the oil and water to separate.

3. Add a few drops of food colouring and watch as the colour sinks through the oil. Pay attention to see if the drops of colour mix with the water immediately or float in between first.

4. Break the fizzy tablet in half and drop part of it into the bottle – you should start to see the bubbling blobs clearly. To give it a more dramatic effect, you could turn the lights off, drop in the other half of the tablet and shine a flashlight through the lava lamp.

The explanation:

The oil floats on top of the water because it's less dense/lighter than water. The food colouring has the same density as the water, so it mixes with the water. After you dropped in the fizzy tablet, it dissolved, making carbon dioxide. Gas is lighter than water, so it floats to the top.

The air bubbles bring some coloured water with them to the top, but when the air comes out of the coloured water blob, the water gets heavy again and sinks. It does this over and over again until the tablet is completely dissolved.

This is a fantastic way to show your kids the importance of washing their hands, which has never been more vital since the spread of the coronavirus.

What you need: pepper; soap; water; a shallow dish or plate.

What to do:

1. Fill the dish with water and sprinkle some pepper over it.

2. Put your finger into the pepper-water and the pepper should stick to your finger.

3. Wipe your finger clean, put some soap on your finger and repeat step two, but this time, the pepper should move away from your finger. Magic!

The explanation:

The way the pepper behaves is related to the surface tension of the medium you are putting the pepper into. Pepper is hydrophobic, which means it doesn't dissolve in water. Because water molecules are strongly attracted to each other – they have high surface tension – it keeps the pepper afloat.

Adding soap breaks down the surface tension and as the water molecules spread away from the soap, they take the pepper with them. This is the same way that tiny particles behave in water when you wash your hands with soap in comparison to only washing with water.

One to blow younger children's minds is an experiment that turns grapes into raisins. The best part is, you don't even really need to do anything!

What you need: a few grapes; a bowl or plate.

What to do:

1. Put the grapes into the bowl ... and that's it! Let time do the rest of the work. Eventually, the grapes will shrivel up and become raisins.

The explanation:

Well, raisins are just dried grapes. Over time, as the grapes get older, warmer and are exposed to oxygen for longer, they get smaller and shrivel up.

The warmer the grapes are, the more the water evaporates from them, causing them to shrivel.

It'll take around two months for them to look like actual raisins, but they won't be safe to eat.

Sorry, what?! Yes, this sounds completely made up, but it's actually a sciencey way to make some slime.

What you need: a tray with sides; cornflour; water; food colouring (optional); biodegradable glitter (optional).

What to do:

Check out our step by step guide to making oobleck gloop here.

The explanation:

Get talking about the difference between a liquid and a solid. This slime behaves the way it does because the particles of cornflour are suspended in the water.

When you squish it, the particles clump together and act like a solid. But when you let go, the particles spread apart again, and it acts like a liquid.

Get messy with this eruption of froth to teach children about chemical reactions.

What you need: a vase or tall glass container; baking soda; vinegar; food colouring (optional); biodegradable glitter (optional); a tray with sides.

What to do:

1. Put the vase in the tray. The tray is to collect the mess so make sure it's not a special one. Put two to three tablespoons of baking soda in the vase.

2. Add six or seven drops of food colouring and one to two teaspoons of bio glitter.

3. Quickly pour in around half a cup of vinegar and watch the eruption! You can redo the experiment again, adding in different elements like salt or pepper, to see how it looks.

The explanation:

Baking soda is a base and vinegar is an acid, so when they interact, they react.

It happens because they exchange atoms – when the baking soda takes a proton from the vinegar, it transforms into water and carbon dioxide.

Who doesn't love a bit of colour changing magic? This experiment is an easy peasy way of teaching kids about chemistry.

What you need: dish/small plate; milk (whole milk works best); liquid food colouring (three or four different colours); dish soap; a clean cotton bud.

What to do:

1. Pour the milk into the dish to completely cover the bottom of it. It should be about a quarter of an inch deep.

2. Add one drop of each colour of food colouring to the milk – keep the drops close together in the middle.

3. Touch the tip of the cotton bud to the centre of the milk without stirring. Take note if anything happens.

4. Remove the cotton bud and put a drop of dish soap on the opposite tip. Now, place the soapy end in the middle of the milk and hold it there for around 10 seconds. Surprise! You should see the colours burst.

5. Add another drop of soap to the tip of the cotton swab and try again, but in different places in the milk. The colours in the milk should continue to move, even when the swab isn't dipped in.

The explanation:

Milk contains proteins and tiny droplets of fat. Milk fat, like other oils, is hydrophobic – this means it doesn't dissolve in water.

When soap is mixed in, it breaks up and collects the fat molecules, making a connection between the soap and the milk. The fat is then carried by the soap.

The molecules of fat roll around in all directions while the soap molecules 'chase' them to join up. So, the food colouring is moved all over the place, too.

Got some spare change lying around? Down the back of the sofa perhaps? This is a quick one for kids of all ages.

What you need: three dull/dirty pennies; two cups; vinegar; dish soap; paper towel.

What to do:

1. Keep one penny on the side. Put the other two in two separate cups.

2. Pour enough vinegar in one cup to cover the penny. In the other, pour in enough dish soap to cover the penny.

3. Wait at least 10 minutes before removing the pennies and rinsing them with water. Dry them with the paper towel. Compare the three pennies – the penny in vinegar should be shiny.

The explanation:

Pennies get dull because the copper reacts with the oxygen in the air. They combine to create dark chemicals called copper oxides.

The acid in the vinegar dissolves these chemicals, so leaves the copper looking shiny. Soap cleans, but doesn't dissolve copper oxides.

This quick and easy lesson in static electricity can be done with kids of all ages.

What you need: balloons; a wall.

What to do:

1. Blow up a balloon to a medium size for each person taking part.

2. Rub the balloon quickly against your hair, a wool jumper, or some fur, for at least 30 seconds.

3. Put the balloon against the wall and let go. It should stick. If you rubbed the balloon on your hair, it should make your hair rise up, too.

The explanation:

When the balloon is rubbed on the material, it gets covered with little negative charges.

The negative charges are attracted to the positive charges in the wall. So the negative and positive charges attract each other, and the balloon 'sticks' to the wall.

There's a good chance you've seen this before on YouTube already, but it's got the perfect amount of wow factor to impress your kids.

What you need: large bottle of Diet Coke; half a pack of Mentos; a Geyser tube (not essential).

What to do:

1. Be warned – Diet Coke is going to go EVERYWHERE, so make sure you're in the garden or somewhere you don't mind making a mess.

2. Stand the bottle of Diet Coke upright and remove the lid. Put the Geyser tube, or some sort of funnel on top so you can drop the Mentos in at the same time.

3. Drop the Mentos into the bottle of Diet Coke at the same time and then ... RUN! A huge squirt of frothy liquid should come blasting out of the bottle.

The explanation:

Diet Coke is fizzy because of the carbon dioxide in it. The gas doesn't get released until you pour the liquid out, so most of the gas is built up inside the bottle, waiting to come out.

Dropping something into the liquid breaks up its surface tension and allows bubbles to form on the surface area of the Mentos. As Mentos are covered in tiny dimples, they have an even bigger surface area, which means even more bubbles form.

But why Diet Coke? Well, it's thought this drink works best because it has slightly different ingredients that make it less sticky than other fizzy drinks.

Get your arty hats on to create some paper towel masterpieces. This is more arts and crafts than science, so it's best for little ones.

What you need: washable markers (not permanent as the colour needs to run when wet); paper towel; paintbrushes; water.

What to do:

1. Get a clean sheet of paper towel and scribble all over it with different coloured marker pens. It looks best when as much of the white space is filled in as possible.

2. Place the paper towel on a hard surface that won't absorb water.

3. Wet the paper towel with water by brushing it on. The colours will start to bleed and merge together to create a whole new piece of art.

4. Once covered in water, hang the sheet up to dry somewhere where the colour won't drip on anything – garden clothesline is best. Voila!

The explanation:

This is a lesson in water absorption. When the towel is wet, the colours spread because the water molecules cling to the sugar molecules in the towel.

Ever thought about combining your efforts to get the kids to eat fruit with science? It's foolproof! Although, we wouldn't recommend this for anyone with a sensitive tummy.

What you need: an orange, clementine or other citrus fruit; half a teaspoon of baking powder.

What to do:

1. Cut the orange/fruit into slices or sections.

2. Eat one slice and take note of how it feels on your tongue.

3. Dip another slice into the baking powder and take a bite. As you chew, it should feel bubbly in your mouth. Don't eat too much of the baking powder, as it's not good for your tummy.

The explanation:

The orange has citric acid in it, while baking powder is known as a base – bases and acids are opposites.

As the citric acid and baking soda mix, loads of carbon dioxide bubbles are produced.

Younger kids in particular will love making their own crystals and observing the shapes in them under a microscope.

What you need: a quarter of a cup of Epsom salt; a quarter of a cup of hot water; food colouring; a cup; a plate.

What to do:

1. In a cup, stir together the Epsom salt and hot water. If the salt doesn't dissolve, give the cup a quick whizz in the microwave.

2. When all of the salt has dissolved, put a couple of drops of food colouring in the cup and stir.

3. Put the cup in the fridge. Within four hours, crystals should have formed in the bottom of the cup, but it's best to check on it every hour.

4. Scoop the crystals onto a plate using a fork and check out the interesting shapes under a magnifying glass.

The explanation:

More salt dissolves in hot water than cold, so the salt that dissolved in the water crystallises when it cools in the fridge.

This is an ideal experiment if you've got some stale bread lying around. It'll teach the kids how yeast and fungus work.

What you need: bread; a few food bags.

What to do:

1. Place one slice of bread in a food bag and put it in the fridge. Place another slice of bread in another food bag, to put in a dark place. Another slice of bread in a bag can go somewhere warm and in the sun, while the other can stay on the worktop.

2. Monitor the slices of bread everyday to see which one goes mouldy first. You'll have to make sure no one thinks it's a snack and puts it in their mouth!

The explanation:

Mould and bacteria grow best in warm, moist conditions, so the mouldiest slice of bread should be the one in the warm spot.

It should also be more mouldy in the dark spot as the mould's reproduction mechanism works faster in the dark.

The least mouldy slice should be in the coolest, driest place.

Okay, so the balloon in this experiment WILL pop eventually, but not when your little one expects it to!

What you need: a balloon; two pieces of tape about two inches long; small needle or pin.

What to do:

1. Blow up a balloon and then use the two pieces of tape to make an 'X' on it.

2. Push a needle through the middle of the 'X'. Time how long it takes for the balloon to pop.

The explanation:

Catastrophic crack propagation – that's what makes a balloon pop. It means that the hole in the balloon opening is what makes it pop, not the pin prick.

When the balloon's hole expands, it rips and the balloon pops. The tape slows down the process.

You could try using different size and shape balloons to see if there's any difference, too.

Have a go at creating your own sweetie rainbow in a glass, while learning a lesson about density and dissolving.

What you need: a mug; a clear glass; five cups; water; Skittles; a spoon; a dropper or pipette.

What to do:

1. Separate the Skittles by colour into the cups like this: two red, four orange, six yellow, eight green and 10 purple.

2. Heat a mug of water in the microwave until the water is hot, but not boiling. Pour two tablespoons of hot water into each cup, over the Skittles.

3. Stir each cup of water carefully. Keep stirring them every 10 minutes, until the sweets are dissolved and the water is room temperature.

4. Slowly and carefully add the coloured water from the cups to the clear glass using the dropper. Do purple first, then green, yellow, orange and red, in that order.

Ta da! You've got yourself a rainbow.

The explanation:

Skittles are mostly made of sugar, so when you add hot water the sugar dissolves and the colouring on the shell of the Skittles turns the water different colours.

The cup with two red Skittles doesn’t have as much sugar as the one with 10 purple Skittles, but they both have the same amount of water. This means the red water is less dense than the purple water and will float on top of the purple water.

This is a fantastic way to show kids how important it is to look after their bones with calcium.

What you need: meat bones; water; vinegar; two glass jars; two labels; a pen or pencil.

What to do:

1. Wash the meat bones you have from your leftover dinner so they're totally clean.

2. Pour water into one jar and vinegar into the other. Label the jars so you know which is which.

3. Place the bones into each jar and leave them for a week.

4. Rinse the bones and try to bend them. Notice a difference?

The explanation:

Bones are filled with calcium carbonate and they become weak when the calcium carbonate reacts to the vinegar.

Bones need calcium to stay strong, but when the make up of calcium is altered, it becomes weak and bendy.

Recreate how a cloud works without even stepping outside in this experiment.

What you need: a large glass; shaving foam; water; food colouring; a spoon.

What to do:

1. Fill the glass half full with water.

2. Spray shaving foam on top of the water so the glass is three quarters full. With the spoon, evenly spread the shaving foam out over the top of the water.

3. In a separate container, mix half a cup of water with around 10 drops of food colouring.

4. Gently add the coloured water, a spoonful at a time, to the top of the shaving foam. Keep an eye out to see what happens when it gets too heavy.

The explanation:

The shaving foam acts as the clouds in this experiment. Clouds can hold a LOT of water, but when they get too heavy, it comes out as rain, snow, sleet or hail.

Shaving foam can also hold water, so you could time how long it takes for the coloured water to fall through into the clear water underneath.

This lesson in sound travel couldn't be simpler to do or explain to kids of any age.

What you need: one balloon.

What to do:

1. Blow up a balloon so that it's filled with air, but don't tie it at the end.

2. Hold the balloon up to your ear and lightly tap on the other side of it. Take note of the sound and vibrations.

3. Let go of the balloon. Take note of which way the air escapes and which direction the balloon moves in.

The explanation:

You push air molecules into the balloon when you blow into it. The air molecules are forced into a small area, so are very close together.

This means they can carry sound better. That's why the tapping is so clear and loud.

Get to know about weight and air resistance with this homemade parachute trick, ideal for younger kids.

What you need: a plastic bag; scissors; string; a small object that has some weight (like an action figure).

What to do:

1. Drop your object from a height and time how long it takes to fall.

2. Cut out a large square from the plastic bag. Trim the edges so it looks like an octagon (eight sides).

3. Cut a small hole near the edge of each side. Then, attach eight pieces of string (all of the same length) to each of the holes.

4. Tie the pieces of string to the object with weight.

5. Drop it from the same height as step one and time how long it takes this time.

The explanation:

The object should fall slowly when it has the parachute attached. When you drop it, the weight pulls down on the string, which opens up the large surface area of the parachute.

The larger the surface area, the more air resistance and the slower the parachute will drop. Cutting a small hole in the middle of the parachute allows air to slowly pass through it, which should help the parachute fall in a straight line.

Making a rain gauge is a classic way to monitor the weather – and in the UK, you're bound to get plenty of data to monitor!

What you need: large plastic bottle; scissors; duct tape; sand; permanent marker; ruler.

What to do:

1. Make sure the plastic bottle is clean. Cut off the spout from where the curve begins.

2. Fill the bottom of the bottle with half an inch of sand. It'll stop the bottle from falling over on windy days. (You can also just use some dirt from the garden.)

3. Pour enough water into the bottle to just sit above the sand. This is your saturation point.

4. Use the permanent marker to draw a line at the saturation point above the sand and write 'starting point'.

5. Put a ruler from the starting/saturation point and draw a line for every inch up to the top of the bottle.

6. Take the spout you cut off the bottle and turn it upside down. Insert it into the bottle and secure it with duct tape. Ta da! You've got a funnel for the rain to fall into your bottle.

7. Find a good place for your rain gauge outside to record the rainfall.

The explanation:

You can check the gauge every day to monitor how much rain falls every 24 hours.

Take it a step further by calculating the average rainfall for the week.

Witness the seasons changing in a matter of a minutes by playing with chemistry and the colour of leaves.

What you need: three green leaves from the same tree; rubbing alcohol; one glass jar; cling film; paper strip from a coffee filter; small bowl filled with hot water.

What to do:

1. Tear all of the leaves into tiny pieces and put them in the jar.

2. Pour rubbing alcohol over the leaves until they're just about covered.

3. Stir the leaves until the rubbing alcohol has gone a bit green. Then, cover the jar with cling film.

4. Put the jar in a bowl of hot water for around 50 minutes. Give the jar a gentle shake every 10 minutes.

5. Take the cling film off and put one end of the paper strip into the rubbing alcohol. Make sure the other end is near the top of the jar and let it sit in there for an hour.

What do you notice?

The explanation:

The rubbing alcohol and hot water separates the colours in the leaves. You probably saw green and depending on your leaf type, red, yellow, or orange.

Chlorophyll is the name of the pigments in leaves that give them their green colour. It's so dominant that it hides the other colours in the leaves.

In autumn, chlorophyll in the leaves breaks down allowing the other colours to be seen.

We're sure the kids will want to give this experiment a go if there's chocolate involved ...

What you need: small pieces of chocolate that are the same size; plates.

What to do:

1. Put one piece of chocolate on a plate and place it in direct sunlight.

2. Time how long it takes for the chocolate to melt, or see how soft it's become after 15 minutes.

3. Do the same with another piece of chocolate, but this time place it in the shade.

4. Keep repeating the experiment, placing the chocolate in different places each time. You could even put one in your mouth! You could also reverse the test, by putting the melted chocolate into the fridge.

If you have a thermometer to hand, taking the temperature of each piece will make the experiment even more interesting.

The explanation:

At a certain temperature, the structure of the chocolate changes when it moves from a solid into a liquid.

The hotter it is, the faster the chocolate will melt because its particles are moving further away from each other.

This is a simple way to test if an egg is raw or cooked, that doesn't include breaking them open to find out!

What you need: two eggs – one hard boiled and one raw, and both at room temperature.

What to do:

1. Spin both of the eggs at the same time – one should spin while the other wobbles.

2. You can also lightly touch the eggs while they're spinning – one should stop quickly while the other keeps moving.

The explanation:

The centre of gravity of the egg changes as the white and yolk move around inside the shell, which makes it wobble. It continues to wobble after you touch it because of inertia. This is the same type of force you feel when you change direction or stop suddenly – your body wants to move one way while the other force moves another way.

When the egg is cooked and more solid, it will wobble less because the particles are more tightly packed.

A great way to teach kids about how plants grow AND get them into a green-fingered hobby.

What you need: seeds of your choice – these can be from leftover fruit and veg or from a packet; soil; a container to hold the plant; water; access to light and heat.

What to do:

1. Fill the container with soil and plant the seeds in it.

2. Put the container somewhere warm with a bit of sunlight, like a windowsill. Although, try to avoid too much direct sunlight.

3. Water the soil as often as the seeds require – it'll probably be around once a day. There should be instructions on the packet or online.

4. Watch your plant grow. You could record your observations everyday for how the plant has changed and when you start to see seedlings.

The explanation:

Seedlings should start to be seen after a week or so. Germination is the name of the process when the plant starts to emerge from a seed.

Water and oxygen are required for seeds to germinate. It depends on the type of seeds you have, but most plants should grow at just above room temperature.

Surely we've all run our finger around the rim of a glass and listened to the ringing noise? But did you ever think about the science behind it?

What you need: five or more glasses/bottles; water; wooden stick or pencil.

What to do:

1. Line the glasses up next to each other and fill them with different amounts of water. The first should have just a little bit of water and gradually each glass has more in it than the last.

2. Hit the glass with the least amount of water and take note of the sound, then hit the glass with the most water and take note.

3. Hit the other glasses to see how their noises compare. You could even try playing 'guess the song' by hitting the different glasses in a tune.

The explanation:

The glass with the most water in it will have the lowest tone while the glass with the least water will have the highest.

Small vibrations are made when you hit the glass, which creates sound waves that travel through the water. The more water there is, the slower the vibrations and the deeper the tone.

What happens when you turn a glass of water upside down? Well, in this trick, the water stays in there!

What you need: a glass of water, filled right to the top; a piece of cardboard.

What to do:

1. Put the cardboard over the top of the glass so that no air bubbles can get in.

2. Turn the glass upside down, still holding the cardboard secure. You might want to do it over a sink or outside, just in case.

3. Take away your hand holding the cardboard and it should stay as you left it.

The explanation:

Even though the glass is upside down, the water stays in place because there's no air inside the glass.

The air pressure from outside the glass is greater than the pressure of the water inside the glass. The extra air pressure holds the cardboard in place, so the water doesn't fall out.

This is an insight into density where the kids can nibble on the equipment afterwards ...

What you need: an orange; a deep container or bowl; water.

What to do:

1. Fill the container with water.

2. Put the orange in the container and take note of what happens. Does it sink or float?

3. Remove the orange, peel it and try again. What happens this time?

The explanation:

When you put the orange in before peeling it, it should have floated on the surface of the water. After you peeled it, it probably sunk.

That's because the rind of an orange is full of tiny air pockets, which give it a lower density than water, making it float. When you take the rind off, therefore removing the air pockets, the density of the orange is higher than that of water, making it sink.

Get your secret agent on as you write hidden messages to each other in this experiment ...

What you need: half a lemon; water; spoon; bowl; cotton bud; white paper; lamp or other small light source.

What to do:

1. Squeeze some lemon juice into the bowl and add a few drops of water. Mix them together with a spoon.

2. Dip the cotton bud into the mixture and write a message on the white paper.

3. Wait for it to dry so it becomes completely invisible.

4. When you are ready to reveal the message, heat the paper by holding it close to a lightbulb.

The explanation:

Lemon juice oxidises (chemically combines with oxygen) and turns brown when it's heated.

Because you diluted the lemon juice with water, it makes it hard to notice when you apply it the paper.

You could also have a go with orange juice, honey, milk, onion juice, vinegar or wine.

Air starts to act differently at different temperatures, and this is a perfect way to show your kids how.

What you need: empty bottle; balloon; hot water (not boiling).

What to do:

1. Stretch the mouth of the balloon over the mouth of the empty bottle.

2. Put the bottle in a pot of hot water, let it stand for a few minutes and take note of what happens.

The explanation:

You've made your own hot air balloon! As the air inside the balloon heats up, the molecules in the air move faster and further apart from each other, causing the balloon to expand.

So, the amount of air inside the balloon and bottle is still the same – it's just expanded because warm air takes up more space than cold air.

It's more scientific than it sounds, we promise. You'd think it would be impossible to pierce a raw potato with a paper straw, surely? Find out how playing with air pressure changes that.

What you need: stiff paper drinking straws; a raw potato.

What to do:

1. Hold a paper drinking straw by the sides, without covering the holes, and try to stab the potato with it.

2. Get a new straw and repeat the first step, but this time put your thumb over the hole at the top.

The explanation:

No, you haven't gained super strength. Placing your thumb over the hole at the top of the straw allows you to properly pierce the potato.

Covering the top traps the air inside, so it pushes outwards on the edge of the straw and keeps them stiff as you stab the straw through the potato skin. On the first attempt, the air is pushed out of the straw, so the straw collapses.

We're told to avoid wearing black on a hot, sunny day and this experiment in heat absorption is the perfect way to explain why.

What you need: two identical glasses or jars; water; thermometer; two elastic bands or sellotape; white paper; black paper.

What to do:

1. Wrap the white paper around one of the glasses and secure with the elastic band/sellotape.

2. Do the same with the black paper and the other glass.

3. Fill the glasses with the same amount of water.

4. Leave the glasses out in the sun for a couple of hours before measuring the temperature of the water in each. The water surrounded by black paper should be hotter.

The explanation:

Dark surfaces (the black paper) absorb more light and heat than lighter ones (the white paper).

Lighter surfaces reflect more light, so that's why people wear lighter coloured clothes in the summer.

This is another quick and simple lesson in static electricity.

What you need: a dry plastic comb; a tap; clean, dry hair on your head.

What to do:

1. Turn on the tap and let it run on a very thin stream of water.

2. Brush your hair 10 times with the plastic comb.

3. Bring the comb close the the flowing water, without touching it. The stream of water should bend towards the comb.

The explanation:

When you brushed your hair, the electrons in your hair collected on the comb. The electrons have a negative charge, so are attracted to things with a positive charge.

When you bring the negatively charged comb near the tap, it's attracted to the positive force of the water, so pulls it towards itself. You can do the same thing by rubbing a balloon against your hair.

Why are sunsets red? This magical trick is another way to demonstrate how the light spectrum works.

What you need: a large clear container filled with five litres of water; 50ml milk; a bright, strong light source like a spotlight or projector lamp.

What to do:

1. Pour 50ml of milk into the container of water. It might work best if you only add a little at first, trying the experiment and then adding more if you can't see the effect.

2. Turn the spotlight on and darken the room. Face the light towards the milky water.

3. The mixture near the torch will look white, but if you look on the other side of the container, the colour should be a mixture of orange and red. Magic!

The explanation:

White light is made up of all of the colours of the rainbow (the light spectrum). When light travels through a substance, some of the different light wavelengths are absorbed while others are reflected.

As the light was shone onto the milk solution, the lower energy wavelengths of orange and red passed through it, creating the orangey red colour of the sunset.

The sky appears blue because blue light is scattered towards us. However, during sunset, the blue light is scattered away from our eyes leaving the oranges and reds.

The kids will love finding out what's 'sticky' around the house with their very own, homemade magnet. However, adult assistance will be necessary.

What you need: a large iron nail (about three inches); three feet of thin coated copper wire; a D size battery; tape; paper clips and other small magnetic objects.

What to do:

1. Wrap the wire around the nail, leaving about eight inches of wire loose at each end. Try not to overlap the wire as you wrap it.

2. Remove about an inch of the plastic coating from both ends of the wire and attach the ends of it to both ends of the battery with tape. Warning – it might get hot, so after the experiment is over, remember to disconnect the wires.

3. Put the point of the nail near a few paper clips and it should pick them up. Ta da! You've made your own electromagnet.

The explanation:

Magnets that can be turned on and off are called electromagnets. They run on electricity, so they're only magnetic when the electricity is flowing.

The electricity flowing through the wire makes the molecules in the nail attracted to certain metals.

Take control over a ketchup packet by making it float or sink at your command, while learning about buoyancy and density.

What you need: one litre plastic bottle, with the labels removed; small ketchup packet; salt.

What to do:

1. Fill the bottle right up to the top with water and put the ketchup packet in it.

2. If the ketchup floats, go to step three. If the ketchup sinks, go to step four.

3. For the floating ketchup packet, screw the cap on the bottle and squeeze the bottle hard. If the ketchup sinks when you squeeze it and floats when you release it, that's it! If it doesn't sink when you squeeze it, try a different kind of ketchup or sauce packet.

4. If the ketchup packet sinks, add about three tablespoons of salt to the bottle. Put the cap on and shake it until the salt dissolves.

5. Continue adding salt, a tablespoon at a time, until the ketchup is floating to the top of the bottle. Once it's floating steadily, make sure the bottle is filled to the top with water, and then tightly fasten the cap.

6. Squeeze the bottle. The ketchup packet should sink when you squeeze the bottle and float up when you release it.

The explanation:

There is a little bubble inside of the ketchup packet and bubbles float, so that keeps the ketchup from sinking. Adding salt to the water adjusted the water's density to get the ketchup to float, too.

When you squeeze the bottle, you're putting pressure on the packet so the bubble gets smaller and the packet gets more dense than the water, causing it to sink.

When you release the pressure, the bubble expands, which makes the packet less dense so it can float back up.

We've all tried hiding sweets from the kids, but with this experiment, it really will disappear in front of their eyes.

What you need: liquorice, a strawberry pencil or another long, straight sweet; a tall, skinny glass; vegetable or olive oil.

What to do:

1. Pour some oil into the glass.

2. Put the sweet into the glass and lean it against the side.

3. Look at the side of the glass and slowly turn it. Does the sweet get wider and narrower? Does it disappear altogether?

The explanation:

Oil bends light even more than water does. So much so, that if you hold the glass in a particular way, the sweet will be completely hidden from your eyes.

Of course, the sweet is still there, but the light is being refracted so you can't see it properly.

It's never been more important to wash your hands than it is now, but it can be tricky trying to explain that to kids. This (pretty gross) experiment will help them understand.

What you need: three pieces of white bread; three clean jars; water; a magnifying glass.

What to do:

1. Touch a small corner of one of the pieces of bread, place it in the first jar and screw on the lid.

2. Sprinkle a bit of water on another piece of bread and leave it outside for 20 minutes. Place it in the second jar and screw on the lid.

3. Sprinkle the third piece of bread with water, then rub it between your hands and along the kitchen worktops. Place the piece of bread in the third jar and screw on the lid.

4. Place the jars in a dark, warm place and check on them every few days. DON'T forget about them!

The explanation:

Over time, the bread in the first jar shouldn't look that much different. The second jar should have some growth on it. The third jar should have some clear mould growing on it.

That's because that piece of bread was covered in bacteria from your hands and surfaces. It was also made wet, which creates an ideal environment for mould to grow.

This is both a challenge and an experiment – can you make a structure that holds the weight of a heavy book, just out of sweets and toothpicks?

What you need: 10 Gumdrops, Winegums, or other sweet that is firm but squidgy; 20 toothpicks; a ruler.

What to do:

1. It's up to the children to try and build a structure from the sweets and toothpicks that'll be able to hold a book on top of it.

2. You can give hints and instructions depending on their ages.

3. They can keep going until they succeed, or you could set a time in which they have to complete their design.

The explanation:

This should encourage them to plan their design and think about what shapes, sizes and layers are more sturdy in a structure.

Take a look here at what the end result might look like.

This will have a lot of wow factor with minimal effort on your part, for kids of all ages.

What you need: a clean jar; water; one teaspoon of dish soap; one teaspoon of vinegar; biodegradable glitter (optional).

What to do:

1. Fill the jar with water until there's about an inch of space at the top.

2. Pour in the vinegar, dish soap and glitter, and secure the lid of the jar shut.

3. With one hand on top of the jar and the other underneath, swirl it around for about five seconds. Then, set it down and watch the tornado go!

The explanation:

When you swirl the water in the jar, it creates a vortex. As the water spins, centripetal force causes the water to spin around that vortex, which makes it look like a mini tornado.

The lungs are important organs for mammals, including humans. This is a good way to show children how lungs work and why we need them to survive.

What you need: a plastic bottle; a paper straw; an elastic band; scissors; two balloons; playdough.

What to do:

1. Cut the bottle to about half the size.

2. Tie a knot in one end of one balloon and cut off the bigger end.

3. Stretch the balloon around the bottom of your cut plastic bottle.

4. Put a straw in the neck of the other balloon and secure with an elastic band. Be sure not to crush the straw, as the air must flow through.

5. Put the straw and the balloon into the neck of the bottle and use the playdough as a seal, to secure it to the bottle.

6. Hold the bottle and pull the knot of the balloon at the bottom. The balloon inside the bottle should inflate, and deflate when you let go.

The explanation:

When you pull the knotted balloon, it creates more space inside the bottle. Air comes through the straw to fill the space, so the balloon inflates. This is similar to how the lungs fill with air when the diaphragm contracts.

When you let go, the space goes again, so the balloon releases the air back out through the straw. Inside our lungs are a network of tubes which allow air to pass though, in a similar (although much more complicated) way.

Learning about the pH scale is one for older children, as they'll be able to understand the function of acids and alkalis better.

What you need: three or four red cabbage leaves; blender; around 400ml of warm water; a sieve; a jug; drinking glasses; substances to test like lemon juice, vinegar, washing-up liquid, baking soda or milk.

What to do:

1. Tear up cabbage leaves and place in the blender. Cover the leaves with warm water.

2. Blend the cabbage and water until the water turns dark purple. If you don't have a blender, finely chop the cabbage, pour boiling water over them and allow them to cool.

3. Pour the contents of the blender through a sieve, collecting the purple liquid in a jug.

4. Pour about 50ml of the purple liquid into a glass and add some vinegar. Watch the liquid change colour.

5. Repeat step four, but add different substances each time, to a fresh glass. This is where you can find out which substances are acids and which are alkalis.

The explanation:

Blending the cabbage leaves with warm water is a quick way to extract the pigment in it that gives the cabbage its red colour.

The pigments change their colour depending on the pH of the solution they're in. They go pink or red when mixed with acidic substances like lemon juice or vinegar, and they turn blue, green or yellow when mixed with alkaline substances like baking soda or washing-up liquid.

You might've already tried to explain to your kids how bad fizzy drinks are for their teeth, but this experiment will really make it hit home.

What you need: eggs; vinegar and/or a selection of soft drinks like orange juice, cola, energy drinks etc; water; a glass or mug for each drink; labels; a toothbrush.

What to do:

1. Put an egg into each glass/mug and cover each one with a different drink. The egg needs to be completely covered.

2. Put one egg into a glass/mug and cover it with water – this acts as the control.

3. Label each glass/mug with what drink is in them and leave them overnight to see what effect the drinks have had. You could leave them for a week to see even more dramatic results.

4. Remove each egg to examine the shell and compare it to the one in water. Rub the shell gently with the toothbrush to simulate the effect of brushing your teeth after exposure to the acidic drinks.

The explanation:

Egg shells are made of calcium carbonate – a mineral similar to what our teeth are made of. Acids react with calcium carbonate. The more acidic a liquid is, the faster the reaction and the more the shell will weaken.

The bubbles that form on the egg are carbon dioxide gas. Orange juice is high in citric acid and has a more dramatic effect than cola! Fizzy drinks usually have acids added to them to give them an extra buzz.

Have fun creating a paper hand to see just how our joints and fingers work, courtesy of Fizzics Education.

What you need: a hand template; scissors; paper straws; tape or glue; string.

What to do:

1. Cut out the hand template and bend the paper where the knuckles are.

2. Cut up the straws to mimic the bones in your hand. You'll need five pieces for the palm, about four inches long, and around 14 smaller pieces (an inch and a half) for the fingers.

3. Glue or tape the straws in place, without squashing them. Leave one centimetre gaps between the straws where the knuckles are so the fingers can bend.

4. Tape 30cm pieces of string to the top of the fingers and thumb. Then, thread the string through each straw, down each finger.

5. Add one straw at the wrist to thread all the strings down it. Hold the edge of the paper and gently pull on the strings at the wrist. Your creation should move like a real hand.

The explanation:

Each hand has 19 bones in it. The bones in each finger and the thumb are connected to the metacarpals, which are the five bones in your palm.

Without so many bones, we wouldn't be able to move our hands in all the different ways we can. There aren't any muscles in our fingers, only our palms and forearms. They move the tendons in our fingers, which control the bones.

No one likes a brown apple or avocado, but why do they go brown in the first place? Find out how to stop them turning bad here ...

What you need: one apple; 175ml lemon juice; a glass of water; a sharp knife; three bowls.

What to do:

1. Cut the apple so you have three thin slices and put each one into a separate bowl.

2. Leave one bowl as is, pour water into the second bowl and lemon juice in the third. Pour enough liquid in each one so that the apple is covered.

3. Leave the bowls for at least 30 minutes and then take note of how each slice of apple looks.

The explanation:

When you cut an apple, the cells inside it are exposed to the air. When oxygen enters the cells of the apple, it reacts with some of the chemicals in them to make a brown chemical product. The process is called oxidation.

The apple in the bowl without liquid goes very brown, because there's no barrier between the apple cells and the air.

The apple covered with water goes less brown because the water is in the way of the cells, however, there is still oxygen in water.

The apple covered in lemon juice goes the least brown because lemon juice contains vitamin C. Oxygen prefers to react with the vitamin C, so it will do this first before it starts browning the apple.

Adult supervision is a must for this fiery experiment from Fizzics Education that tests how hot air works. Make sure you're well away from anything flammable when you do it!

What you need: a teabag that's stapled shut (regular teabags don't work); matches; a non-flammable plate.

What to do:

1. Cut the top of the teabag to remove the staples.

2. Pour the dry tea onto the plate and flatten them out.

3. Open the teabag so it forms a cylinder and place it on top of the dry tea so it stands upright, like a column.

4. Carefully light the top of the cylinder on fire and watch it rise.

The explanation:

When you lit the cylinder, you created a convection current of air moving inwards, towards the burning teabag, and rising up as a hot air column. The 'rocket' can only rise once the teabag becomes lighter.

Heating air makes the molecules move around quickly and become more separate from each other, in turn making it less dense. The less dense substances rise above more dense ones, so the hot air rises above the cold air.

Who doesn't love bubbles? Find out why they can look like they have mini rainbows in them.

What you need: washing up liquid; salt; a plastic bowl; a paper straw; a bright torch.

What to do:

1. Mix a few squirts of washing up liquid with water and a pinch of salt.

2. Coat the bottom of the plastic bowl with the mixture.

3. Use the straw to blow a bubble on the surface you just coated.

4. Shine a torch on the bubble from the side and spot the rainbow.

The explanation:

White light is made up of many colours that each have different wavelengths – that's why rainbows are always in this colour order: red, orange, yellow, green, blue, indigo, violet.

The surface of bubbles breaks up the white light into the colours it's made up of.

This is a simple way of making funny sounds that'll keep the kids entertained for hours.

What you need: a styrofoam or plastic cup; a metal slinky.

What to do:

1. Push the end of the metal slinky through the base of the cup.

2. Hold the top of the cup so the slinky dangles towards the floor.

3. Gently shake the cup from side to side to create some interesting sounds. You could also try bouncing it up and down.

The explanation:

When you move the cup, you're transferring vibrations up the slinky into the cup, which also then vibrates.

The metal vibrates against the cup and creates the buzzing noise, where the rest of the sound is formed by the sounds echoing within the cup. The amount of air in the cup means the sound is louder.

Have a chat via an underwater telephone to hear how water affects sound.

What you need: two plastic funnels; rubber tubing that will fit the funnels; one balloon; a paddling pool or other large container of water (a bath will do).

What to do:

1. Attach the funnels to both ends of the rubber tube.

2. Stretch the balloon over the end of one of the funnels. It needs to be tight across the funnel opening.

3. Place the funnel with the balloon into the container of water. Place the other funnel over your ear. What do you hear? If someone else can get under water to talk through the funnel, what do they sound like?

The explanation:

The balloon picks up the vibrations travelling through the water. As the balloon starts to vibrate, it amplifies the sound.

This is how sea creatures like whales communicate with each other from up to 100 miles away! The sound travels faster through water than it does air because molecules in liquid are more tightly packed than in gas.

Change the colour of flowers with this nifty trick. It'll teach kids how plants 'drink' water.

What you need: different colour food colouring; plants with white petals, like carnations or daisies; scissors; four jars of water.

What to do:

1. Mix each jar of water with a different food colouring. The solution will need to be quite strong, so don't hold back on the colour.

2. Cut the bottom of the stems off of each flower, then place each flower into each jar so the stem is in the solution but not the petals.

3. Wait and watch the petals change colour.

The explanation:

Plant stems have tubes inside them called vascular bundles. Water from the leaves and petals of plants evaporates in the air, so the water must be replaced.

The coloured liquid is being pulled through the stem by the vascular bundles to replace the lost water in a process called transpiration. The food colouring in the water changes the colour of the petals and leaves.

Take it a step further by splitting one stem in half and placing each half in a different colour solution to make the flower go two different colours.