27 Scientific Experiments for Children

The scientific experiments they are one of the best ways to explain concepts of biology, chemistry or physics to children, in a dynamic, practical and interesting way. In addition, they can show the usefulness of the subjects that the children study.

Although education has traditionally been based on a unidirectional relationship -the teacher explains and the student receives information-, teaching is more effective when it is dynamic, practical and the student knows the usefulness of what he learns.

We are going to show a list of experiments that you can practice with children. It is always important that as an adult you are present to avoid possible incidents and explain what needs to be done.

Scientific experiments with water

Water is a natural and vital element for the human being. From very young, people are in contact with this natural resource.

However, very rarely are you aware of the chemical reactions that can be experienced when this liquid is mixed with other substances.

Domestic rainbow

With this experiment we will show how a rainbow can be created in the home.

Materials needed for the experiment:

• A glass of water
• A spray bottle
• A piece of paper
• Sunlight

Procedure to follow:

The first thing to do is place a glass of water on a table, chair or window where the sunlight reaches.

Then a sheet of paper should be placed on the floor / ground, just at the point where the sunlight reaches, in the path of the line of the glass vessel.

Subsequently, warm water is sprayed in the place where the sun enters. All elements must be aligned. Including the paper that was placed on the floor.

Locate the glass and paper in such a way that a rainbow forms.

In this video You can see an example.

Ice fishing

With this experiment a small"trick"will be shown to lift ice cubes with a string, using only salt.

Materials needed for the experiment:

• Small paper cup
• Bowl or tray with ice cubes
• 1 glass of water
• Thread, rope or string about 15 or 20 centimeters long
• Salt

Procedure to follow:

The first thing to do is fill a cup with water and put it in the refrigerator. They also work ice cubes that are usually in the refrigerator.

Once the ice cube is ready, it should be placed in the glass with water. This cube will float.

One end of the rope (which would simulate a fishing rod) is placed on top of the bucket. Sprinkle with salt just the point where the ice and the rope meet.

It will be noticed that for a few seconds, the water melts but immediately freezes again.

Wait about 10 seconds and then carefully lift the ice cube, pulling the string or thread. It will be like catching a frozen fish.

Why does this happen?

What happens in this experiment is that the salt lowers the freezing temperature of the water and, as the ice is already as cold as it can be, it starts to melt.

This melting forms a kind of well on the surface of the ice, which favors the temperature of the freezing point to rise again.

Then, the ice freezes again and the rope or thread is trapped inside the ice cube.

Running water freezes at 32 ° F.

In this video You can see how to do it.

The mirror method

In this experiment the physical principles of reflection and refraction are demonstrated.

When the light waves pass through the water, a slight bending occurs in the direction of those waves.

And when hitting the mirror glass, there is another deviation that allows the reflection of the colors of the rainbow.

Materials needed for the experiment:

• A small mirror
• A glass of water (in which the mirror can be held)
• A flashlight
• A small room
• A piece of white paper or a white wall

Procedure to follow:

The first thing that is done in this case, is to place a mirror inside a glass of water.

Then you have to make sure that the room is completely dark.

Now, it's time to light a flashlight (or direct the rays of sunlight), and light up the mirror.

A series of mini rainbow will appear on the mirror.

If the hand is placed on the base of the glass and the light is directed to that point (which crosses the glass with water), the colors of the rainbow will also be seen.

In this video You can see how to do the experiment.

Fold the water with static energy

What is demonstrated with this experiment is the operation of static electricity.

The negatively charged particles (electrons) that are naturally in the hair, pass to the comb or balloon, leaving it with an extra charge of electrons.

On the other hand, water is neutral because it has particles with positive and negative charge, but when approaching the object with extra negative charges, its positive charge reacts and moves the current in that direction.

Materials needed for the experiment:

• A plastic comb (or an inflated balloon)
• A narrow stream of water from a tap
• Dry hair

Procedure to follow:

The first thing to do is open the water tap a little, so that the current that comes out is a few millimeters wide.

Now, the child should slide the comb along the hair at least 10 times

In the event that instead of a comb, a balloon is being used, it should be rubbed back and forth on the hair for a few seconds.

Now, you should gently bring the comb or balloon towards the water stream (without touching it).

You will see how the water bends to reach the comb or the balloon.

In this video You can see how to do it.

Without gravity

With this experiment it will be shown that it is possible to modify the force of gravity, because the pressure of the air outside a vessel is greater than the pressure of the water inside it.

The extra air pressure holds the cardboard in place and the water inside the cup.

Materials needed for the experiment:

• A glass of water (overflowing)
• A piece of cardboard

Procedure to follow:

The cardboard should be placed over the mouth of the glass cup. It is important that no air bubbles enter between the water and the cardboard.

Now, turn the glass upside down. This is done over a sink or a place where it does not matter if you throw in a little water.

Once the glass is turned over, the cardboard is left holding the hand.

You will see with amazement that the cardboard does not fall and the water does not spill. There is no gravity!

You can see how to do it in this video .

Recreation of a cloud

It will show how a Rain cloud forms with drops of water that result from the collision of cold air with water vapor that has risen after the evaporation of terrestrial water bodies.

When these clouds accumulate a lot of water, the water returns to the ground in the form of rain.

Materials needed for the experiment:

• 1 jar
• Tap water
• Shaving foam
• Food coloring of blue color
• Glass dropper

Procedure to follow:

The procedure to follow is to fill the jug with running water. With the shaving foam, a kind of cloud is spread on the surface of the water.

Wait a few minutes for the foam to settle and then add a few drops of the blue dye.

The foam will begin to drip the colorant on the water and a rain effect will be created.

You can see how to do it here .

Walking water

It will show the phenomenon that occurs in the transport of water and nutrients within flowers and plants.

This happens due to capillary action, which is the name given to the process by which a liquid moves through a conduit.

This can also be an opportunity to talk to children about primary and secondary colors.

Materials needed for the experiment:

• 2 paper towels
• 3 transparent glasses
• Food coloring yellow and blue.

Procedure to follow:

The three glasses should be aligned together. In the first glass, water should be poured with abundant blue dye.

The next glass is left empty and the last one in the row is filled with water and the yellow dye is added to it.

It is time to fold the paper towels and place them in the mouth of the glasses; one end is placed in the glass with blue water and the other end is dropped on the empty glass placed in the middle.

The operation in the yellow water vessel is repeated; one end of the towel inside and the other end in the empty glass.

In about 30 minutes, the water will pass through the paper towels to the empty glass, and after 2 hours, the middle glass will have a green liquid.

In this video You can appreciate how to do it.

Dry ice bubble

In this experiment it will be shown that Carbon dioxide (CO2) in its solid form is dry ice.

When dry ice reaches temperatures above -56.4 ° C (-69.5 ° F), it becomes a gas. It never goes through a liquid state. It is the phenomenon called sublimation.

Put dry ice in contact with water, accelerates the process of sublimation and produces clouds of fog.

Materials needed for the experiment:

• Water
• A large container with a lip around the top
• A strip of cloth
• Liquid soap for washing dishes
• Dry ice (this requires the participation of an adult who takes safety measures)

Procedure to follow:

The dry ice is placed in a container and a little water is added. At this point the scene may resemble that of a Disney movie about witches preparing a brew.

Prepare a little soapy mixture, joining a little liquid soap to wash dishes with water.

Now the piece of cloth is soaked in the soapy mixture and passed over the edge of the container. Then, it goes through the upper part so that bubbles form on the dry ice.

The bubble will start to grow.

In this video you can watch it

Musical water

In this experiment we will show how to create sound waves traveling through the water. In the glass with more water the lowest tone will be produced, while in the one with less water the highest will be produced.

Materials needed for the experiment:

• 5 or more glasses (they also serve glass bottles)
• Water
• Wooden stick or pencil

Procedure to follow:

The glasses or flasks are aligned so that a row of glasses is formed. Water is added to these in different quantities so that the first one has very little water and the last one is full.

With the pencil or another wooden bar, hit the edge of the glass with less water and then repeat the operation on the edge of the glass with more water.

Different tones of the sound will be noticed. If done in a specific order, you can get a musical melody.

See how to do it in this video .

Scientific experiments with balloons

Technically speaking, a balloon is nothing more than a container made of a flexible material such as aluminized plastic or rubber. Normally it is filled with air but can also be filled with helium.

Usually used, at least in the West, as the decorative element of the holidays. It also results in a fun toy for children.

Below are some experiments that can be done with balloons and that give a more scientific touch to their use.

More space for air

With this experiment it will show how to As the air inside the balloon heats up, it begins to expand in response to the separation that arises between the molecules because they begin to move faster.

This means that hot air needs more space.

Materials needed for the experiment:

• Empty bottle
• Balloon
• Container with warm water

Procedure to follow:

The balloon should be placed over the mouth of the empty bottle.

This bottle should be placed inside the container with hot water. Let it rest for a few minutes and you will see how the balloon begins to expand.

Watch in this video how to do it.

Propulsion balloon

In this experiment it will be shown that When vinegar and sodium bicarbonate are combined, a gas is produced that generates a pressure strong enough to blow up a balloon.

Materials needed for the experiment:

• 1 empty plastic bottle
• ½ cup of vinegar
• Sodium bicarbonate
• Teaspoon
• Recycling paper
• Permanent marker
• 1 balloon
• 1 scissor
• 1 glue stick

Procedure to follow:

On the clean side of the recycling paper, draw a shirt to glue it to the front of the bottle in which the 1/2 cup of vinegar will be poured.

With the permanent marker, draw a face on the balloon and with a small spoon, pour the baking soda into it.

It is time to stretch the neck of the balloon around the neck of the bottle. We must ensure that the sodium bicarbonate stays inside the balloon.

Once the balloon is secured in the bottle, the baking soda is dropped in the vinegar.

The balloon (and the face that was drawn on it), will grow.

You can see in this video how to do it.

Experiment with baking soda

He sodium bicarbonate It is a type of salt that is formed from carbonic acid. It contains a hydrogen atom that can be replaced by a metal.

Normally, their domestic uses are related to helping in the preparation of spongy cakes or eliminate heartburn when consumed diluted in water (in minimal doses).

It is also used in the preparation of grains (such as beans, for example), to avoid gas in people with irritable bowel.

But here are some experiments in which their chemical properties are revealed.

Volcano experiment

What you see in this experiment is the chemical reaction between an acid (vinegar) and an alkaline (bicarbonate of soda). They try to neutralize each other.

During this reaction, carbon dioxide, which is a gas, is released. Next to water and soap, that explains the bubbles.

Materials needed for the experiment:

• 2 tablespoons of baking soda
• 1 tablespoon of liquid soap
• a few drops of red dye
• 30 ml vinegar
• 1 bottle of water

Procedure to follow:

In a conical shaped container or a small prop volcano, add the dye, soap, water and baking soda.

All this is mixed and before adding the vinegar, it goes back.

Now you can pour the vinegar and enjoy the artificial volcanic eruption that has just been created.

You can see how to do it in this video .

Experiments with magnets

A magnet is a material or body that has magnetic force thanks to which it can attract other magnets and ferromagnetic metals.

The magnet can be natural or artificial. The latter can have their magnetism for a specific time or indefinitely.

These elements have multiple uses; as a component of electronic equipment or devices, in the magnetic strips that have credit and debit cards, as part of the decoration of the home (in the ornaments that are usually placed in the refrigerator), etc.

Below are some simple experiments in which children can discover the strength of these objects.

The compass

It will show that the earth works like a huge magnet that attracts all metals to its north pole.

Materials needed for the experiment:

• Water
• 1 bowl, glass or container
• 1 compass
• 2 small pieces of paper or cork
• 2 needle magnets

Procedure to follow:

The first thing to do is to float a small sheet of paper in a container or glass of water.

On that piece of paper or cork, you must place a needle magnet.

Now, you must repeat the operation with the second needle magnet.

The two needles must point in the same direction. Then, the terrestrial magnetism will make the magnet point to the north.

To be sure, find a point of reference that allows you to locate the north (your shadow may be useful), and identify the needle-magnet that is pointing north.

Watch in this video how to do it.

Experiments with air

Air is the mixture of gases that is in the Earth's atmosphere and that allows human life. Although it is not seen, it is vital for human survival and development.

For years, man has investigated its properties and the forces that affect it to take advantage of it in different fields of industry.

Unfortunately, it is also a natural resource that is being negatively affected by pollution.

In this section you will see some simple experiments that show the presence and power of air.

The magic ball

In this case, the interaction between the force of the air flow of the dryer and the force of gravity that pushes the ball toward the ground is observed.

The tension between the two forces keeps the ball in the middle and seems to float.

Materials needed for the experiment:

• 1 small ball (like ping pong)
• 1 hair dryer

Procedure to follow:

In this simple experiment it is enough to turn on the hair dryer and direct the air flow up, trying not to be hot air.

In the path of that air flow, the ball must be released.

The child will see with amazement how the ball floats.

Watch in this video how to do it.

The submarine

In this experiment the air pressure operates.

When the cigarette or straw is thrown into the bottle, the air inside makes it float, but when pressed, the interior space is compressed and the pressure on the cigarette is increased by sinking it into the water.

When the pressure is released on the bottle, the child stops pressing it, the air pressure on the straw decreases, it is filled with air again and can now float.

Materials needed for the experiment:

• 1 empty soda bottle without the label
• 1 plasticine bar or some clay
• 1 straw
• Water

Procedure to follow:

It begins by cutting a cigarette to which plasticine is placed on one of its ends, so that this hole is covered.

At the opposite end, a plasticine ring is placed bordering or hugging the straw. The goal is to put weight on that end of the straw.

Now add three quarts of water to the bottle and cover it.

Then, children can squeeze the bottle to see how the straw sinks and release it, so that it returns to the surface of the water to swing. This operation can be repeated as many times as you want.

Watch in this video how to do it.

Experiments with plants

Paint the flowers

Materials needed for the experiment:

• 3 cups with water
• 3 artificial colors
• 3 white flowers

Procedure to follow:

You should add to each cup with water, several drops of the same color, so that each cup has a different color from the other.

The stem of each flower is cut and immersed in the cup of water that has just been colored.

The children will notice that the flowers are absorbing the water through its stem and progressively changes the color of its petals and leaves.

Why does this happen?

In this experiment, the transport function of the stem in the plants is demonstrated, and how the nutrients (in this case replaced by the colored water) travel through the plants to promote their growth and development.

Watch in this video how to do it.

Grow, the little plant grows

Materials needed for the experiment:

• Ruler or tape measure
• Seeds of cucumber, sunflowers and basil
• Three pots (can be more if you have enough space and different seeds)
• Earth
• Water
• Paper
• Pencil or pen

Procedure to follow:

To begin, you must add soil in the pots. Then the seeds should be placed there (for each pot, a type of plant).

The pots should be placed in a space where they receive sunlight.

After a reasonable period of time, it must be verified which of the pots already has germinated seeds.

Once the first stem emerges, the measurement begins. To do this, use a ruler or a tape measure and record the name of the plant, the date and the height.

This operation is repeated every week.

After three weeks, you will begin to notice that each plant has a different growth rate.

Likewise, it will be verified that each type of plant can reach a specific height.

It is an experiment that requires patience so creativity is necessary to encourage children to persevere in measuring.

Maybe a photo session with your favorite plant, helps keep the interest.

Experiments with eggs

Egg float

Materials needed for the experiment:

• 1 egg
• Water
• 6 tablespoons of salt
• 1 tall glass

Procedure to follow:

The glass should be filled halfway with the water. Then, add the 6 tablespoons of salt.

Now, add running water until the glass is almost full.

It's time to introduce the egg to the water and see what happens. If the tap water is not mixed abruptly with the salt water, the egg will tend to float on the surface of the salt water, more or less in the middle of the glass.

Why does this happen?

In this experiment the density is shown.

Salt water has a density greater than that of running water.

The denser a liquid is, the more likely an object is to float on it.

Watch in this video how to do it.

Dissolve the shell of an egg

Materials needed for the experiment:

• 1 egg
• A little white vinegar
• 1 thick glass jar with lid (and wide mouth)

Materials needed for the experiment:

Insert the egg into the glass jar. For a child, it may be easier to do this by flipping the jar a little so the egg slides into it.

Now, you can add the vinegar, making sure there is enough to cover the egg.

The egg may float, but it will only be for a moment because then it sinks.

In a minute or two, small bubbles of carbon dioxide will appear in the egg shell. The bottle should be covered and left to rest for a week.

The vinegar can be replaced in that time.

At the end of this time, it is very likely that a layer of foam forms on the surface.

It will be seen that the egg has increased its size a little and that its brown color begins to pale.

It is time to remove the egg from the vinegar.

At this point, there is only a little shell that can be cleaned with a gentle rub. If this does not happen, it should be soaked for longer in vinegar.

Why does this happen?

In this process, the phenomenon of cellular osmosis is evidenced in which a liquid passes through a semipermeable cell membrane.

The calcium bicarbonate in the egg shell dissolves in the acidic medium of the vinegar. However, vinegar is a mild acid that does not dissolve it immediately without doing it very little by little.

In the process, the calcium bicarbonate is transformed into calcium acetate.

Observe it in this video .

Experiments with food

The potato and the arrow

Materials needed for the experiment:

• Several straws or rigid plastic straws
• 1 raw potato

Procedure to follow:

To start this experiment, it is necessary to make a test first: hold the cigarette without covering the hole in its upper end and throw it towards the potato as if trying to stab it.

It will be a useless effort because the potato can not be penetrated. And if it is achieved, it will only be a few millimeters.

Now, it's time for the real experiment:

You try to do the same with the potato, but this time you cover the hole in the upper end of the straw with your thumb.

On this occasion I should drill a larger space of the potato.

Why does this happen?

What happens is that by plugging the hole in the cigarette, the air inside is compressed and this serves as an impulse to reach the potato with more force.

A force that manages to penetrate the skin of the potato and its pulp.

Watch in this video how to do the experiment

Orange float

Materials needed for the experiment:

• 1 orange
• 1 deep container
• Water

Procedure to follow:

It is necessary to begin by pouring water into the container. Then, the orange is thrown into the water.

The next part of the experiment is to do the same but on the second occasion it must be done after peeling the orange peel.

What this experiment reveals is that the orange has air in its shell, which helps to increase the density of the water and to float on its surface.

When peeling the orange, however, the density of the orange increases and the denser material sinks into the water.

Watch in this video how to do the experiment

Art with milk

Materials needed for the experiment:

• A bowl
• ½ cup of milk
• Dishwashing soap
• Cotton swab (cutex or hyssop)
• Various food coloring

Procedure to follow:

Pour the milk into the bowl and wait a few minutes for it to settle and the surface of the milk to stabilize.

Add drops of different colored dye at different points in the milk.

Moisten one end of the swab with some of the soap and apply gentle touches over the colored gots.

You will see how funny figures are formed and you can enjoy works of art.

It should be noted that this milk will not be suitable for consumption after this experiment.

Why does this happen?

This reaction is due to the fact that the milk has a high fat content and the liquid of the dyes floats on the fat.

Dishwashing soap cuts the bonds in the fats and separates them, and the color that was added makes that separation more visible.

There are variations of this experiment when the temperature of the milk changes and when different types of milk are used.

Another thing that can be done is to add pepper on the milk before touching its surface with the swab moistened in soap.

Watch in this video how to do it.

Magnetic cereal

Materials needed for the experiment:

• Cereal
• Neodymium magnet
• 1 transparent bottle
• Water

Procedure to follow:

Fill the bottle with water up to a third and add the cereal. The bottle is covered and shaken vigorously.

The cereal is left to"soak"during a whole night in such a way that it softens and breaks.

When the cereal is completely wet and in smaller pieces, place the magnet on the outside of the bottle, ensuring that there is more liquid at the point where the magnet is.

Then, turn the bottle so that the water is not directly below the magnet.

Slowly, remove the magnet and you will see the pieces of iron attached to the bottle.

Why does this happen?

In cereals there is a certain iron content, and when it is broken into smaller pieces or soaked in water, that content is more exposed.

The magnet will attract those metallic traces with its magnetism.

Watch in this video how to do it.

Lava lamp

Materials needed for the experiment:

• Water
• A transparent plastic bottle
• Vegetable oil
• Food coloring
• Alka seltzer

Procedure to follow:

Fill the plastic bottle with water until it is a full room. A funnel can help make this step without spilling too much fluid.

Now, you finish filling the bottle with vegetable oil.

Let the mixture stand for a few minutes until both liquids separate.

Little by little, about twelve drops of food coloring are added. The color of that dye can be any.

The dye will mix with the water and will become a liquid of the favorite color of the"scientific child".

Now, the Alka-Seltzer tablet (5 or 6) is cut into pieces, and one of those pieces is thrown into the bottle with the mixture.

The effervescence will turn the bottle into a lava lamp.

Why does this happen?

Water and oil do not mix very well. In fact, because of its density, the oil stays on top of the bottle.

The dye goes directly to the bottom and mixes with the water. The Alka-Seltzer releases carbon dioxide bubbles.

These bubbles rise to the top charged with colored water. The reaction ends when the gas reaches the surface and releases the water from the bubble.

Every time you add an Alka-Seltzer tablet to the bottle, you will see the same reaction. And shake the bottle back and forth, it will prolong the duration of the reaction.

Watch in this video how to do the experiment

Experiments with different materials

Miniature rockets with teabag

Materials needed for the experiment:

• A tea bag
• A lighter
• A fire-resistant tray
• A bag of garbage

Procedure to follow:

Cut one end of the tea bag and empty its contents. With the freshly cut bag, a cylinder is formed and placed in the tray.

Now, with the help and supervision of an adult, the upper part of the tea bag is turned on. I should take off.

Why does this happen?

This happens because the flow of hot air blows up the small mass of the tea bag.

Watch in this video how to do it.

Liquid layers

• Some juice
• Vegetable oil
• Alcohol
• A transparent container

Procedure to follow:

Take the container and pour the juice. On the juice, the vegetable oil is added little by little but in such a way that it slides along the walls of the container.

Now, it's time to gently pour alcohol. The alcohol can be pure or colored.

It will be seen that the liquids are separated into three layers.

Why does this happen?

This happens because the substances in this experiment have different densities. The result can be more aesthetic if the liquids are colored separately.

Watch in this video how to do it.

Tornado in a bottle

• Two transparent bottles
• A tube
• Some water

Procedure to follow:

The water is poured into one of the bottles and connected to the other by the nozzle with the tube (it can be a PVC or plastic tube).

Turn the liquid in the bottle located on the top. When you start to drain the liquid to the other bottle, a vortex is created.

Why does this happen?

This happens because as the water circulates downwards, the air is forced to go upwards.

This process generates a spiral tornado.

If you want to add a different touch, you can add brightness, food coloring or lamp oil.

You can observe a variant of this experiment in this video .

Overweight rubber bears

Materials needed for the experiment:

• A bag of rubber bears
• 4 glasses
• A teaspoon of salt
• A teaspoon of baking soda.
• Measuring tape
• Kitchen scales
• Pencil and paper (to take note of physical changes during the experiment).

Procedure to follow:

You have to take the glasses and pour 50 milliliters of water to each of them.

One, it is left alone with water; to another vinegar is added; to another is added the teaspoon of salt; and to the fourth, the teaspoon of baking soda is added.

Now, each teddy is measured and weighed and the data is recorded, identifying them very well so that it can be detected if a change occurs or not.

Then, each bear is introduced into a different glass and there they are left to soak for a whole night.

At dawn, the bears are removed from the glasses and left to dry.

Now, each bear is measured and weighed a second time and the data is compared.

Why does this happen?

Here also the phenomenon of osmosis is noted.

Look in this video .

Balance holders

Materials needed for the experiment:

• Two forks
• A toothpick
• A long glass
• A lighter.

Procedure to follow:

It should start by coupling the two forks.

Then, the stick is passed through the first hole of one of the forks and is removed by the second hole of the other as if it were a fabric.

Now, the forks are placed with the interlaced stick on the edge of the glass. That is, the toothpick will rest on the edge of the glass, while supporting the weight of the forks in a delicate balance.

It is time to light a fire at the end of the stick that is inside the glass (with supervision and assistance from an adult).

The fire will consume the stick, but the forks will remain in balance.

Why does this happen?

It deals with the balance provided by the location of the center of mass.

In this case, the center of gravity is located below the point of support.

Watch in this video how to do it.