20 easy science experiments for kids

Volcano | Floating fish | Lava lamp | Magic milk | Egg vinegar experiment | Grow crystals | The rainbow jar | Dancing raisins | Elephant toothpaste | DIY compass | Invisible ink | Sticky ice | Egg drop | Chromatography | Balloon cars | Skittles experiment | DIY puffy slime | Mouldy bread experiment | Walking rainbow experiment | Water bottle chimes

Volcano

You will need:

• An empty plastic bottle
• 2 A3 sheets of card
• Pencil
• Scissors
• Tape
• Paint
• Paintbrushes
• Small bowl
• Cup
• 1 tbsp bicarbonate of soda
• 1 tbsp washing-up liquid
• 2 tbsp water
• 1/2 cup vinegar
• 1 tbsp red food colouring

Step-by-step instructions

To make the volcano:

1. Place the bottle upside down on a piece of A3 card and draw a circle around the neck
2. Draw a straight line from the edge of the card to the circle, then cut it out
3. Make a cone shape with the card by overlapping the 2 edges and then tape into place
4. Cut around the base of the cone so it's flat, but ensure that it's taller than the bottle
5. Place the cone over the bottle and tape the top to the neck of the bottle
6. Tape the base of the cone to the other A3 piece of card
7. Have fun painting the cone to make it look as volcano-y as you can!
8. Leave to dry

To make the explosion:

Tip: We recommend you create the explosion outside due to the mess!

1. In the bowl, mix together the bicarbonate of soda and washing-up liquid
2. Add the water and mix thoroughly then pour this mixture into the volcano bottle
3. In the cup, mix together the vinegar and food colouring
4. Pour the vinegar mixture into the bottle
5. Step back and watch it erupt!

Credit: Natural History Museum

Floating fish

You will need:

• A bowl
• Tap water
• A metal spoon
• Dry erase markers (make sure the marker is NOT washable, washable markers will not work)

Step-by-step instructions

1. Fill the bowl with water
2. Use the dry erase marker to draw a fish shape on the back of the metal spoon (tip: press down so a lot of ink comes out, try to draw thick lines and make sure all the lines are connected to each other)
3. Slowly and carefully dip the spoon into the water, try to shake the ink off gently so it doesn't break
4. Alternatively, you can draw on the bottom of the dish and slowly add water into the dish to see if the dish release and float

Credit: Best Ideas for Kids

Lava lamp

You will need:

• Funnel
• Water
• Empty, clean plastic bottle
• Red food colouring
• Fizzy vitamin tablet
• Vegetable oil

Step-by-step instructions

1. Pour water into the bottle using the funnel until it's one-third full
2. Add a few drops of the red food colouring
3. Use the funnel to fill the rest of the bottle with vegetable oil
4. Break the vitamin tablet in half and add into the bottle
5. Watch as the lava starts to bubble!

Credit: Science Museum Group

Magic milk

You will need:

• Whole milk
• Flat plastic tray
• Food colouring in a range of different colours
• Cotton buds
• Washing-up liquid
• A cup

Step-by-step instructions

1. Pour the milk into the plastic tray so that just the bottom is covered
2. Carefully put a drop of each colour of food colouring near the middle of the tray (use as many different colours as you like!)
3. Pour a small amount of washing-up liquid into a cup, then dip the tip of the cotton bud into it to coat it
4. Gently put the bud to the surface of the milk
5. Watch the colours swirl!

Credit: Science Museum Group

Egg vinegar experiment

You will need:

• 1 raw egg
• Clear glass
• Vinegar
• Gloves

Step-by-step instructions

1. Gently place the raw egg in a clear glass and cover it with vinegar
2. Leave the egg for about 48 hours (tip: you can speed up the process by changing the vinegar halfway through)
3. Put the gloves on, remove the egg and gently rub the eggshell away
4. Carefully drop the egg from a couple of centimetres above the ground
5. Watch it bounce!

Grow crystals

You will need:

• Water
• Pan
• 600g sugar
• Food colouring
• Craft stick (or ice lolly stick)
• Clothes peg
• Clear glass

Step-by-step instructions

1. Pour 250ml of water into your saucepan and bring it to a boil
2. Once it's boiling, stir in the sugar, ⅓ (200g) at a time, until it's completely dissolved
3. Once the sugar is boiling, remove it from the heat
4. Optional: stir in food colouring
5. Allow the mixture to cool for 15 minutes
6. Clip the clothes peg to the stick and place the stick in the jar
7. Wet the stick by dipping it in a glass of water, then coat with a layer of sugar and allow to dry
8. Pour the now-cooled sugar mixture into a clear glass
9. Place the stick into the middle of the glass, adjust the peg so it rests on the top of the glass, with the end of the stick resting half an inch from the bottom of the jar
10. Leave the jar for about 5 days so the crystals can grow
11. Carefully break the surface of the sugar with the spoon until you can pull out the stick
12. Transfer the stick to a clean, empty glass
13. You then have finished, sugar crystals!

Credit: The Good and the Beautiful Homeschool Science

The rainbow jar

You will need:

• Tall, clear glass or container
• Honey
• Red, blue and green food colouring
• Mixing bowls
• Blue or clear washing-up liquid
• Vegetable oil
• Water
• Rubbing alcohol/surgical spirit
• Gloves

Step-by-step instructions

1. Pour honey into the tall, clear glass to make a layer about 2cm thick (pour it slowly and evenly into the centre of the jar)
2. In a small bowl, combine a drop of red and blue food colouring and a few drops of water to make a purple colour
3. Mix the purple colour completely into the honey and let it settle for 1 minute
4. To create the blue layer, either use blue washing-up liquid or mix clear washing-up liquid carefully with a drop of blue food colouring
5. Slowly add to the jar to make a second layer about 2cm thick
6. In another bowl, mix a drop of green food colouring with a few drops of water (or mix green and yellow food colouring together)
7. Tilt the jar, slowly pour the green water in to make another layer that's about 2cm thick
8. Wait a few seconds, then tilt the jar and slowly pour enough vegetable oil to make another 2 cm-thick layer
9. Mix red food colouring with a small amount of rubbing alcohol/surgical spirit thoroughly
10. Carefully pour it into the jar to make another layer about 2cm thick

Credit: Ontario Science Centre

Dancing raisins

You will need:

• A handful of raisins
• A jar of water
• A freshly opened, clear fizzy drink poured into a glass (lemonade or soda water)

Step-by-step instructions

1. Drop a handful of raisins into the jar of water and watch them sink to the bottom
2. Drop a handful of raisins into the fizzy drink and watch them dance! They should rise to the surface, then sink and rise again

Credit: Science Foundation Ireland

Elephant toothpaste

You will need:

• Clean and dry a 500ml plastic bottle
• Bowl
• Funnel
• 125ml 3% hydrogen peroxide
• A small amount of washing-up liquid
• Food colouring
• 2 tbsp warm water
• 1 tsp fast-action yeast
• Small jug

Step-by-step instructions

1. Put the plastic bottle into a non-reactive bowl (or oven dish)
2. Put a funnel in the top of the bottle, then slowly and carefully pour in the hydrogen peroxide
3. Remove the funnel straight into a sink or bowl (make sure you don't drip any hydrogen peroxide that might still be in it)
4. Add a squirt of washing-up liquid to the bottle
5. Add a few drops of food colouring to the bottle, then gently shake the bottle to mix the ingredients together (make sure to keep the bottle upright)
6. Stir the yeast and warm water together in a small jug
7. To do the experiment, pour the yeast mixture into the bottle and move away quickly
8. Watch as the mixtures react together and burst out of the bottle

DIY compass

You will need:

• Piece of foam
• Scissors
• A long needle
• Magnet
• Non-metallic bowl of water
• Real compass

Step-by-step instructions

1. Cut out a small cube of foam, about 1/2 inch long on each side
2. Lay the needle flat against a magnet and rub the magnet one way against the needle, repeat 20 times (make sure you always run the magnet in the same direction)
3. Stick the needle all the way through the piece of foam so it sticks through the other side
4. Float the foam and needle in your bowl of water, the needle should lie parallel to the surface of the water
5. Place your real compass on a flat surface next to the bowl and watch what happens, the needle should turn until one ends points north and the other end points south

Credit: American Museum of Natural History

Invisible ink

You will need:

• Half a lemon
• Small bowl
• Thin paintbrush
• Paper
• Iron
• Ironing board

Step-by-step instructions

1. Squeeze the lemon juice from the lemon into a bowl
2. Dip the thin paintbrush into the lemon juice and write a message on the piece of paper (tip: the more lemon juice you use, the darker the message will appear)
3. Leave the paper to the side and wait 15-20 minutes for the juice to dry
4. Once the juice is dry, place your paper on the ironing board
5. On a high heat, iron the paper until the secret message is revealed (this should take 15-30 seconds)
6. Let the paper cool and read your secret message!

Credit: The National Archives

Sticky ice

You will need:

• Ice cube tray
• Water
• Food colouring (optional)
• Bowl
• Salt
• String

Step-by-step instructions

1. Fill the ice cube tray with water, if you have food colouring, add a few drops into each cube
2. Place in the freezer (tip: this may take some time so try freezing the night before)
3. Once the ice cubes have frozen, place a few ice cubes in the bowl
4. Fill the bowl with just enough cold water to cover the ice cubes
5. Lay the string across the bowl, make sure it's lying across an ice cube
6. Sprinkle some salt on top of the string and ice, and wait for at least 1 minute
7. Pull the string up and watch as the ice cube sticks to the string!

Egg drop

You will need:

• 3 glasses
• Water
• Cork-backed placemat
• 3 hollow tubes
• 3 hard-boiled eggs

Step-by-step instructions

1. Arrange the 3 glasses in a triangle formation and fill them half-full with water
2. Balance the placemat on the glasses with the cork side facing upwards
3. Balance the hollow tubes on the placemat (open end up) and make sure they are directly over the glasses
4. Balance the eggs on top of each of the three tubes
5. Hit the placemat hard from the side with a flat open palm...
6. See what happens!

Credit: Science Museum Group

Chromatography

You will need:

• Non-washable felt-tip pens
• Kitchen roll
• A bowl/cup
• Water
• Scissors

Step-by-step instructions

1. Take a sheet of kitchen roll and draw a simple picture with the felt-tip pen
2. Place the sheet over an empty bowl or cup
3. Carefully add a few drops of water using your fingertips or a small paintbrush onto the drawing
4. Once slightly damp, watch the picture on the kitchen roll to see the different colours spread out

Credit: Royal Society of Chemistry

Balloon cars

You will need:

• 3 flexible straws
• Scissors
• Tape
• Clean and empty plastic bottle
• 2 wooden skewers
• Hobby knife
• 4 bottle caps
• Balloon
• Rubber band

Step-by-step instructions

1. Cut two straws so they are slightly longer than the width of your plastic bottle
2. Tape the two straws across the bottle, make sure they are parallel
3. Cut the skewers so they're slightly longer than the straws
4. Use the hobby knife to make small holes in the centre of four bottle caps
5. Push a skewer through one of the holes in the bottle cap
6. Pointy end first, thread the skewer through one of the straws
7. Push a bottle cap onto the end of the skewer
8. Repeat steps 5-7 and attach to the other straw; you have now made two axles
9. Make sure that the axles spin freely, put the bottle car down and make sure it rolls smoothly — adjust if needed
10. Slide the short end of your third straw into the neck of the balloon
11. Tightly wrap a rubber band around the neck of the balloon
12. Blow the balloon up through the straw (to make sure there are no gaps)
13. Cut a small hole that's big enough for the straw in the top of the car
14. Press the free end of the straw through the small hole and out of the mouth of the bottle
15. Tape the straw so it points backwards, not down
16. Inflate the balloon, then put the car down and release! Cover the tip of the straw with your fingertip to keep the air in the balloon until you put it down

Tip: If the car doesn't move or moves slowly, inflate the balloon more and try again. Also, make sure to check your axles to make sure they spin freely and are aligned with the plastic cap 'wheels'

Credit: Science Buddies

Skittles experiment

You will need:

• Skittles (1 pack)
• Plate or bowl
• Small bowl or cookie cutters (optional)
• Warm water

Step-by-step instructions

1. Arrange the skittles into a simple shape on your plate, or use a small bowl or cookie cutters as a guide
2. When your shape is complete, remove the bowl or cookie cutter (if you've used one)
3. Pour warm water onto the plate, making sure all the Skittles are sitting in a layer of water
4. Keep watching, and the colour from the Skittles should slowly move into the water and make a colourful pattern

See our full Skittles colour experiment guide

DIY puffy slime

You will need:

• 3 cups shaving cream
• Cups to measure out your ingredients
• 1/2 cup PVA glue
• Food colouring
• 1/2 teaspoon baking soda
• 1 tablespoon saline contact solution
• Large mixing bowl
• Spatula
• A plastic container to store your slime

Step-by-step instructions

1. Shake a can of shaving cream well, then tip it down into the 1 cup measure and try to fill the cup completely with shaving cream, then add to the mixing bowl
2. Measure out 1/2 cup PVA glue and add it to the shaving cream in the bowl, mix well until the mixture looks smooth
3. Add in a few drops of food colouring
4. Sprinkle 1/2 teaspoon baking soda over the top and mix well
5. Add 1 tablespoon of saline contact solution
6. Use the spatula to mix it together fairly fast for a minute
7. Keep mixing until the slime is mostly in one blob and has pulled away from the sides of the bowl
8. Knead the slime with your hands (at first, it will be fairly wet and sticky, but as you stretch and knead the slime, it will become firmer and drier, but remain soft)
9. Optional: make another batch of slime with a different colour of food colourin,g then roll it together with the first batch to create swirls of different colours

Credit: Instructables

Mouldy bread experiment

You will need:

• Safety goggles
• Kitchen apron
• Permanent marker
• Gloves
• 5 resealable plastic zip bags
• 5 slices of bread (the fewer preservatives, the better)
• Soap
• Hand sanitiser
• A notebook
• A pen
• A ruler

Step-by-step instructions

1. Use the permanent marker to label the 5 bags as follows:
   1. Control
   2. A surface of your choosing (computer keyboard, kitchen sink, bottom of your shoe, etc.)
   3. Unwashed hands
   4. Soap and water
   5. Hand sanitiser
2. Put the gloves on and put 1 slice of bread in the bag marked "Control". Seal the bag
3. Take another slice of bread and gently wipe it over a surface of your choosing (as written on your 2nd bag earlier), be careful not to tear or smash the bread. Then place the bread in the bag with the same label and seal it
4. Remove your gloves and grab another slice of bread, touch as much of the bread with your unwashed hands, then place it in the bag marked "Unwashed hands". Seal the bag
5. Wash your hands with soap and water for 20 seconds, dry your hands, then grab the next slice of bread and touch it all over. Then place it in the "Soap and water" bag. Seal the bag
6. Touch a few surfaces around the house with your bare hands for about 2-3 minutes, then use hand sanitiser on your hands. Grab the next piece of bread, touch it all over, then placeit in the "Hand sanitiser" bag and seal the bag shut
7. Take your 5 bags of bread and place them in a warm spot
8. Take a picture to document what they look like on Day 1. You could also write down your observations in a notebook, or draw a picture of what your bread looks like
9. Look at the bread every day and take a picture, or take notes in your notebook. If mould starts to appear on any of the bread slices, take a ruler to measure the mould and write this down in your notebook

Credit: Astra Zeneca

Walking rainbow experiment

You will need:

• Several colours of food colouring
• 3 clear plastic cups/glasses of the same size
• Paper towels
• Scissors
• Water

Step-by-step instructions

1. Put a few drops of food colouring in a plastic cup/glass, then fill the rest of the cup about halfway full with room temperature water
2. Repeat this step in another cup with a different colour of food colouring
3. Put your other empty cup in the middle of the two filled with coloured water
4. Cut a paper towel in half, then fold it into quarters lengthwise
5. Put one end of the paper towel in the coloured water and the other end into the empty jar
6. Now use the other halved and folded piece of paper towel by placing one end in the other cup of coloured water and its opposite end into the empty cup
7. You should now see both coloured waters climbing the paper towels and joining in the empty cup

Credit: Science Fun

Water bottle chimes

You will need:

• 4 empty glass bottles
• Water
• A spoon (optional)

Step-by-step instructions

1. Fill up your glass bottles with different amounts of water, increasing each time (i.e. 100ml, 200ml, 300ml, etc)
2. Blow across the top of the bottle, or tap the side of the bottle with a spoon
3. Notice how the pitch changes for each bottle, depending on how much water is in the bottle. When the bottle has a small amount of water, the air molecules have lots of room and vibrate more slowly, producing a deeper sound. When the bottle has more water in it, this means the air molecules have less space to vibrate in, making them vibrate faster and producing a higher pitch

Credit: Science World

Pics: Getty

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