Preschoolers may not fully understand science concepts yet, but doing science experiments is an excellent way to lay a foundation for future learning and exploration. Experimentation helps young children build a good relationship with science by making concepts fun and hands-on.
In this article, we’ve featured simple experiments to teach preschoolers basic science concepts. But before getting into our list, let's discuss why science activities are important and what concepts children need to learn at this stage.
What are important science concepts for a preschooler to learn?
There are seven basic preschool science concepts. They include:
- Observing. This is the first concept children learn from science experiments. For example, when you present them with an object, they are able to use their senses to describe its color, size, shape, and texture.
- Comparing. Once your preschoolers learn to observe items, you can introduce several items for them to compare. For example, which apple is bigger? Are the colors different?
- Classifying. After observing and comparing, preschoolers can progress to grouping items. They can arrange things according to shape, size, texture, or color.
- Measuring. This is a more advanced skill, where preschoolers can practice measuring items for comparison instead of simply comparing the objects through observation. For example, they can use a weighing scale or tape measure to determine which banana is bigger.
- Communicating. After doing experiments, preschoolers have to learn how to report their results. This can be done through documentation, drawing, or verbal description.
- Inferring. Children can learn this skill through simple experiments in the classroom. For example, if your class has a thriving plant that you water consistently, the children might notice it has withered after school has been closed for an extended period of time. The children might come to the conclusion that the plant needs water.
- Predicting. This skill is gained by making guesses based on prior observations. Preschoolers will start by predicting easy concepts, like what melts or what floats, and advance as they learn more.
Importance of science experiments in early childhood
Here are the benefits of introducing science in preschool:
As an early childhood teacher, you are most likely bombarded every few minutes with questions about why things happen. Science allows children to investigate and learn more about the world around them. Encouraging children to engage in exploratory activities can help feed curiosity and even reduce the occurrences of challenging behavior. For example, a paint-mixing activity can help neutralize high energy and avoid distracting behavior.
Enhances the curriculum
Science doesn't have to stand on its own—other parts of the preschool curriculum can be tied to science concepts. For example, during a temperature measuring experiment, children can practice number recognition. You can also extend the lesson by discussing arctic animals or the culture of people who live in cold climates. You could even incorporate an art class by deciding to draw arctic animals.
Boosts literacy development
Group science experiments can boost children’s communication skills. One way this is done is by discussing predictions or observations. Children must also use their critical thinking skills to predict what to expect from the experiments and express their thoughts about the experiment.
Builds a foundation for learning
Science experiments foster a positive attitude toward science at an early age. The skills children learn at this stage can help them think critically, improve their problem-solving skills, and understand their world better. Concepts such as animals, plants, weather, and environment can impact a child's perspective of the world around them.
Science activities for preschoolers
Listed below are our favorite preschool science experiments.
1. Grow a rainbow
The concept behind this experiment is capillary action, which is the spontaneous flow of liquid into a porous material. However, preschoolers don't need to remember that to enjoy the action. Prepare to see their faces light up as the rainbow travels up the paper towel to make a complete rainbow. It's also a good opportunity for children to learn more about colors.
2. Sink or float
In this experiment, children are challenged to predict what will sink and what will float. They can then do the experiment with different objects and record their findings. Remember to ask them to note which predictions they got right.
Additionally, when preschoolers use science-related terms, it expands their vocabulary. For example, science introduces them to words like species, lifecycle, habitat, and microscope.
3. Color-changing milk
This experiment is an introduction to the concept of surface tension, and requires only a few simple materials to get started. There are so many color changes during this experiment, so it's an excellent way to introduce preschoolers to observation and communicating their findings. After the experiment, ask the children when the color changes happened and why they occurred.
4. Water absorption
Understanding how different items absorb water is an important concept for children to understand in real life. This experiment will help preschoolers determine what to use when drying a spill and help them understand why they can use a napkin to wipe up a drop of water, but they need a towel to dry themselves after bathing.
5. What melts in the sun?
This is a good way to pass the time on a hot, sunny day and teach your preschoolers about melting points. Pick a mixture of items that can melt and items that don't melt and add them to a muffin tin. You could choose items such as a cube of cheese, ice, a rock, butter, or a coin. Before starting the experiment, ask the children to predict which items they think will melt and record their answers.
Place the tray in the direct sun and wait at least 15 minutes to see what happens to the items and then revisit their predictions to see which ones they got right. Later, ask them to name other items they think would melt.
6. Bubble towers
This bubble blowing activity will probably be one of your children’s favorite experiments. Add water and a few drops of dish soap to a plastic cup and have children blow out through plastic straws to make bubbles. The bubbles will grow and expand and spill over the edges of the cup. See who can create the biggest bubble tower!
7. Hands-on air pressure
Introduce your preschool class to the concept of air pressure with an experiment that gives a visual demonstration of moving an object with just air. Add two kitchen sponges to a plastic bag and place a plastic straw between the two sponges so one end is outside the bag and one is inside the bag. Seal the bag with tape. Blow into the straw to inflate the bag. Place a pom pom or cotton ball on a flat surface in front of the end of the straw and press hard on the sponges and watch the pom pom roll away.
8. Static comb
This easy experiment teaches the basics of static electricity, the friction force caused by the imbalance of positive and negative charges on a surface. The charges build up on the surface until they’re discharged.
For this activity, take some colored paper and cut it up into small pieces. Scatter the pieces on a table. Grab a plastic comb and hold it over the pieces of paper and see what happens. Next, run the comb against your hair and hold it over the pieces of paper again. The comb will now attract the pieces of paper and they will get attached to the comb.
9. Magic dancing rice
This experiment shows the reactions of acids and bases. You’ll need vinegar, baking soda, a clean container, a spoon, rice, and water.
Pour a cup of water into the container, then add a teaspoon of baking soda and stir. Sprinkle some rice in the mixture and observe what happens (the rice sinks because it's denser than water). Then add a teaspoon of vinegar to the water. You’ll observe that the vinegar reacts with the baking soda to form carbon dioxide bubbles.
After a few minutes, the rice rises to the surface of the glass. Once the rice reaches the surface level, the gas is released, and the rice falls to the bottom of the glass, and the process continues to repeat.
10. Strong shapes
This science activity is similar to the game Jenga, and it’s a good way to introduce preschoolers to the concept of weight distribution. The idea is to make bases of different shapes—square, triangle, and cylinder—out of sheet paper to see how much weight each base can support. Once the bases are ready, you can start stacking items such as books, one by one, on each base to see how it supports the items.
11. Glowing water experiment
This experiment introduces children to electromagnetic waves. For this experiment, you’ll need regular tap water, tonic water, a dark room, a black light, four glasses, fluorescent paint, and a highlighter pen. Fill glass one with regular tap water, glass two with tonic water, glass three with normal water and highlighter ink, and glass four with normal water and fluorescent paint. Put the four glasses in a dark room, place the back light 12 inches away from the glasses, and watch which glasses glow.
You’ll see that glass one doesn’t glow under black light. However, glass two glows brightly because the quinine in tonic water makes invisible ultraviolet rays visible. Glass three glows because highlighter ink contains phosphors, which react to the black light, causing the water to glow. Because fluorescent paint also contains phosphors, glass four will also glow under black light.
12. Egg and toothpaste experiment
Convincing children to brush their teeth can be a challenge. This experiment presents an opportunity to show preschoolers how toothpaste protects teeth from discoloration.
For this experiment, you’ll need a dark soda like Coca-Cola, toothpaste, black coffee, four glasses, and four raw eggs. Pour black coffee into two glasses and pour the soda into the remaining two glasses. Coat two of the eggs with toothpaste. Place one plain egg in a glass of soda and one with toothpaste into the other glass of soda. Then place one plain egg in a glass of coffee and a coated egg in the other glass of coffee. Allow the setup to rest for at least 24 hours for desired results.
You should find that the plain egg in the soda glass stains, while the one coated in toothpaste doesn’t. Similarly, the toothpaste-coated egg in coffee doesn’t stain, but the plain egg in the coffee does.
This happens because when the plain eggs are placed in the liquids, the acidic contents react with the calcium carbonate to form stains. However, when the eggs are covered with toothpaste, the fluoride creates a protective layer around the eggs to prevent the acidic reaction from happening.
13. Ocean in a bottle
This simple experiment introduces children to the concept that water and oil don’t mix. For this experiment, you’ll need a funnel, blue food coloring, cooking oil, water, and a large, clear plastic bottle. Fill the bottle with water and add several drops of food coloring. Ask your preschoolers to shake the bottle to disperse the food coloring and observe what happens.
14. Leak-proof bag
This experiment is fascinating, even for some adults. Did you know that you can push pencils through a bag full of water without the water spilling out? Well, it’s possible because the bag is made of a long flexible chain of molecules (polymers), so when the pencils enter the bag, molecules form a seal around them. You’ll need sharpened pencils and a gallon-size storage bag for the experiment. Fill the bag halfway with water and poke a pencil straight into one side and through to the other side. Allow the preschoolers to try this with as many pencils as they can.
15. Rain cloud in a jar
This experiment allows preschoolers to understand the idea behind water saturation as well as explore clouds and rain in an engaging way. It shows children the process through which clouds get thick before the rain falls.
For this experiment, you’ll need a large jar, pipettes, gel food coloring, and shaving cream. Mix the food coloring with water in a small cup. Fill ¾ of the large jar with water and spray some shaving cream on top to represent a cloud. Ask the children to use the pipettes to squirt the colored water on top of the cream. Soon the colored water will seep down through the cream (cloud) into the water, just like rain!
16. How to keep a tissue dry in water
This activity is a good way to explain how air pressure works. For this experiment, you’ll need a container, cup, water, and tissue. Instruct the children to push the tissue inside the cup and then fill the container with water. Have the children push the cup down into the water while keeping it straight.
When done properly, no water touches the tissue. This is because the air pushes the water away from the cup. Lastly, instruct the children to place the cup inside the water again, tilting it this time. This lets air escape from the cup, allowing the water to wet the tissue.
17. Disappearing eggshell
This disappearing egg experiment is a good introduction to how different chemical agents react. In this case, the eggshells dissolve because they contain calcium carbonate. The latter dissolves in the vinegar to produce carbon dioxide gas and calcium ions.
For the experiment, you’ll need a fresh egg, white vinegar, and a 16-ounce mason jar with a lid and ring. Place your egg in the mason jar and fill the jar halfway with vinegar. It’s important not to completely fill the jar, because the build-up of carbon dioxide could cause the jar to burst. Cover the jar loosely to allow the gas to escape, and let it sit for at least 48 hours.
18. Floating egg
This experiment is a good way to explore the concept of density. You’ll need tap water, table salt, sugar, saline water, four raw eggs, four glass jars, and a tablespoon. Fill four glasses halfway: Fill glass one with water, glass two with salt water, glass three with sugar water, and glass four with saline water. Place an egg in each glass and observe.
You’ll find that the egg in glass one sinks because the egg is denser than tap water. However, the egg in glass two floats because the salt increases the water’s density. Similarly, the egg in glass three floats. The egg in glass four sinks.
19. Dissolve objects
This experiment will help your preschoolers understand items that dissolve in water. When choosing substances for the experiment, be sure to include substances that won’t dissolve. Sugar, cornmeal, flour, oatmeal, orzo noodles, and colored sprinkles are good substances to consider. Encourage the children to predict which substances will dissolve before starting the experiment and compare the predictions with the results after completing it.
20. Thunderstorm formation
This is an interesting introduction to the concept of convection. Convection is the science behind why thunderstorms are more common during the afternoon when the sun heats up moist air near the land that rises into cold air.
For this experiment, you’ll need water, two cups, a container, and two colors of washable paint or food coloring. You can use red with warm water and blue with cold water. In one cup, mix cold water and the blue coloring; in the other cup, mix red coloring and warm water. Then pour the cups of colored water at opposite ends of the container of room temperature water. Observe how the red coloring floats while the blue coloring sinks.This happens because warm water has a lower density than room-temperature water, while cold water has a higher density than room-temperature water. Eventually, the cold water becomes warm and starts to rise. Conversely, the warm water cools and starts to sink. This process is called convection.
It's time to get to the lab
Allowing children to participate in science activities sets a strong foundation for an interest in the subject. Doing experiments at an early age makes children feel capable, encouraging them to embrace scientific concepts throughout life. We hope our list helps you bring a lot of science fun into your classroom. Happy experimenting!