Earth Day Science Experiments and STEM Activities

This Earth Day, let’s celebrate our amazing planet with fun and eco-friendly science experiments! From growing crystals that mimic natural formations to exploring density with colorful liquids, these STEM activities are designed to inspire kids to learn more about the world around them.

With simple materials and an Earth Day twist, each experiment combines hands-on fun with a focus on caring for our planet. So roll up your sleeves, gather your supplies, and let’s honor Earth with science-filled creativity and discovery!

Fun Earth Day Science Activities Using Recycled Materials

Recycled materials offer endless opportunities for creative, hands-on science activities. These projects are perfect for Earth Day because they teach students the importance of reusing materials while exploring key science concepts.

A great starting point is building simple machines or models from common recyclable items. Students can construct bridges, towers, or catapults using materials like cardboard, plastic bottles, and tin cans. These activities promote problem-solving and demonstrate principles such as force, balance, and energy.

Popsicle sticks are another versatile recycled material. Students can use them to design bridges, geometric shapes, structures (like bird feeders) or even small catapults. These projects help introduce concepts like structural integrity and engineering basics. For ideas, explore these STEM projects using popsicle sticks.

Plastic bottles also offer many possibilities. Students can create wind-powered cars, water filters, or plant holders using clean, used bottles. You’ll find more creative ideas in this collection of plastic bottle STEM projects.

Additionally, cardboard tubes and tin cans can be turned into fun, educational builds. Check out these STEM activities with toilet paper rolls and tin can STEM projects for simple, engaging ways to repurpose household items.

For a complete list of ideas, visit this guide to STEM projects using recycled materials. These activities help students celebrate Earth Day while learning about sustainability in a creative, hands-on way.

Homemade Earth Day Play Dough

Celebrate Earth Day by creating eco-friendly play dough in earthy tones! Children can shape globes, trees, leaves, and other nature-inspired designs while learning about chemistry, measurement, and the importance of caring for our planet.

Materials Needed

• 2 cups all-purpose flour
• 1 cup salt
• 2 tablespoons cream of tartar (optional but recommended)
• 1 cup water (approximately)
• 1 tablespoon vegetable oil
• Green, blue, and brown food coloring (or if you want to make this eco-concious: natural dyes such as spinach juice for green, blueberry juice for blue, cocoa powder for brown)
• Optional: A few drops of an earthy scent (e.g., peppermint, rosemary, or citrus essential oil)
• Optional: Leaf-shaped or Earth-themed cookie cutters
• Mixing bowl
• Spoon or spatula

Steps

1. Combine Dry Ingredients
   • In a mixing bowl, whisk together the flour, salt, and cream of tartar (if using).
2. Add Color & Scent
   • In a small cup, mix your chosen coloring—food dyes or natural dyes—into the water.
   • Stir in a few drops of an earthy essential oil if desired.
3. Mix in Wet Ingredients
   • Pour the colored, scented water and vegetable oil into the dry ingredients.
   • Stir until the mixture starts to come together into a dough.
4. Knead the Dough
   • Transfer the dough onto a clean surface and knead it until it’s smooth and pliable.
   • If it’s sticky, add a sprinkle of flour. If it feels too dry, add a few drops of water.
5. Shape & Play
   • Mold the dough into Earth Day shapes like globes, leaves, or flowers.
   • Use cookie cutters or let the kids sculpt freely by hand.
   • Keep the dough in an airtight container to maintain softness.

(Optional Stovetop Method)

1. Combine the flour, salt, and cream of tartar in a saucepan.
2. In a separate bowl, mix the food coloring or natural dye, oil, and scent with the water.
3. Slowly stir the wet mixture into the dry ingredients.
4. Heat on low, stirring constantly, until the dough pulls away from the pan.
5. Remove from heat, knead thoroughly, and create Earth-friendly shapes.

How It Works (The Science Behind It)

• Formation of Gluten: When flour and water mix, the proteins in flour form gluten, giving the dough elasticity and structure.
• Preservation with Salt: Salt helps extend the dough’s shelf life by reducing bacterial growth.
• Cream of Tartar: This acidic powder helps the dough remain softer for longer and stabilizes the gluten network.
• Natural Dyes: Using fruit or vegetable juices introduces plant pigments without significantly altering the dough’s texture.

STEM Concepts Involved

• Chemistry: Observe how combining flour, salt, and water creates a new, pliable substance.
• Measurement & Ratios: Practice careful measurement of ingredients to achieve the right consistency.
• Environmental Awareness: Learn about natural colorings, reducing waste, and caring for the planet through sustainable choices.
• Experimentation: Try different natural dyes or scents and see how they affect the dough’s color, aroma, and consistency.

DIY Earth Day Lava Lamp – Sensory Activity & Density Experiment

Celebrate Earth Day with a simple science experiment that highlights the beauty of our planet! Create a lava lamp inspired by Earth’s blue oceans and green forests. Add eco-themed decorations and teach kids about science and the importance of sustainability with this fun, hands-on activity.

Materials Needed:

• A clear plastic or glass bottle or jar
• Water
• Vegetable oil
• Food coloring (blue and green)
• Effervescent tablets (like Alka-Seltzer) or baking soda and vinegar
• Eco-friendly glitter or biodegradable confetti (optional)
• Stickers or markers to decorate the bottle with Earth, trees, or recycling symbols
• Optional: Flashlight for illumination

Steps for the Activity:

1. Decorate Your Bottle (Optional): Use Earth-themed stickers, draw designs with markers, or tie a green ribbon around the neck of the bottle to symbolize sustainability.
2. Prepare the Base: Fill the bottle about one-quarter full with water.
3. Add the Oil: Carefully pour vegetable oil into the bottle until it’s nearly full. Leave some space at the top.
4. Color the Water: Add a few drops of blue and green food coloring to create an Earth-inspired color palette. The drops will mix with the water but not the oil.
5. Add Eco Sparkle (Optional): Sprinkle in eco-friendly glitter or biodegradable confetti for extra flair.
6. Start the Reaction:
   • If using effervescent tablets, break one into smaller pieces and drop them into the bottle.
   • If using baking soda and vinegar, first add a tablespoon of baking soda to the bottle, then slowly pour in vinegar.
7. Watch the Magic: Observe the blue and green bubbles rise and fall through the oil, creating a mesmerizing Earth Day lava lamp effect.
8. Illuminate (Optional): Shine a flashlight underneath the bottle for a glowing, eco-themed effect.

How It Works:
Water and oil don’t mix because water molecules are polar, meaning they have a slight charge, while oil molecules are non-polar, with no charge. Polar molecules attract each other and exclude non-polar ones, causing the oil to separate and float on the denser water. When the effervescent tablet or baking soda and vinegar react, they release gas bubbles that carry the blue and green-colored water (and glitter or confetti, if used) upward through the oil. Once the gas escapes, the denser water sinks back down, creating the lava lamp effect.

STEM Concepts Involved:

• Density: Why oil floats on water and why they don’t mix.
• Chemical Reactions: Gas production from effervescent tablets or baking soda and vinegar.
• States of Matter: Interactions between solids, liquids, and gases.
• Experimentation: Kids can experiment with different shades of blue and green or add eco-friendly decorations to customize their Earth Day lava lamp.
• Environmental Awareness: Discuss the importance of using sustainable materials and minimizing waste during the activity.

Edible Layers of the Earth

Dig into the Earth’s layers with a deliciously educational experiment. Create an edible model of the Earth’s structure and slice into geology in the yummiest way possible. Click here for the full edible earth experiment.

Build a Mini Greenhouse

Creating a mini greenhouse is a hands-on way for students to learn how plants grow and how the environment affects them. This simple project demonstrates how a greenhouse traps heat and moisture, creating a controlled environment ideal for plant growth. It’s a perfect activity for Earth Day, as it highlights the importance of plants in our ecosystem and introduces students to sustainable growing practices.

Materials Needed:

• Clear plastic containers or empty plastic bottles (cut in half)
• Potting soil
• Seeds (e.g., beans, herbs, or flowers)
• Spray bottle with water
• Scissors (if using plastic bottles)
• Plastic wrap (optional, for extra coverage)

Steps:

1. Fill the plastic container or bottom half of the plastic bottle with potting soil.
2. Plant the seeds according to the instructions on the seed packet.
3. Lightly spray the soil with water to moisten it.
4. Cover the container with the clear lid or plastic wrap to create a greenhouse effect.
5. Place the mini greenhouse in a sunny spot indoors or near a window.
6. Observe the growth daily, watering as needed to keep the soil moist.
7. Record how long it takes for the seeds to sprout and track plant development.

How It Works (The Science Behind It)

The mini greenhouse traps heat from sunlight and keeps moisture inside. This creates a warm, humid environment that helps seeds germinate and plants grow faster. The clear covering allows sunlight in but reduces water loss, mimicking how real greenhouses work to extend growing seasons.

STEM Concepts Involved:

• Plant biology (photosynthesis, germination)
• Ecosystem balance
• Renewable resources (sunlight)
• Environmental science (sustainability and conservation)

Composting Experiment

A composting experiment introduces students to the natural process of decomposition and how organic waste can be recycled into nutrient-rich soil. By setting up a small compost bin and tracking how different materials break down, students gain hands-on experience with sustainability and waste reduction, making this an excellent Earth Day science activity.

Materials Needed:

• Clear plastic container or small bin with lid
• Soil
• Organic waste (fruit peels, vegetable scraps, coffee grounds, leaves)
• Spray bottle with water
• Spoon or small shovel
• Notebook for observations

Steps:

1. Place a layer of soil at the bottom of the plastic container.
2. Add small pieces of organic waste on top of the soil.
3. Mix the waste and soil together lightly with a spoon or shovel.
4. Spray with a small amount of water to keep the mixture moist (but not soaking wet).
5. Cover the container loosely to allow airflow.
6. Stir the compost every few days and observe the changes.
7. Record how long it takes for the materials to break down.

How It Works (The Science Behind It)

Composting relies on the natural process of decomposition. Microorganisms, insects, and bacteria break down organic materials into simpler compounds, producing nutrient-rich compost. This process reduces landfill waste and recycles nutrients back into the soil, supporting healthy plant growth.

STEM Concepts Involved:

• Decomposition and the nutrient cycle
• Microbiology (bacteria, fungi)
• Environmental science (waste reduction, sustainability)
• Observation, data collection, and analysis

Create a Water Filtration System

This activity teaches students how natural and man-made filtration systems clean water. By using simple materials, students will build their own filters and test how well they can remove dirt and impurities. It’s a great way to demonstrate the importance of clean water and how science plays a role in solving environmental challenges.

Materials Needed:

• Clear plastic bottles or cups
• Gravel
• Sand
• Activated charcoal (optional but effective)
• Cotton balls or coffee filters
• Dirty water (can be made by mixing water with soil or food coloring)
• Rubber bands (optional)

Steps:

1. Cut the bottom off a plastic bottle to create a funnel shape.
2. Place a cotton ball or coffee filter at the narrow end to block larger particles.
3. Add a layer of activated charcoal on top (if available).
4. Add a layer of sand above the charcoal.
5. Add a layer of gravel on top.
6. Place the filter over a clean container.
7. Slowly pour dirty water through the filter and observe the water collecting below.
8. Repeat as needed to improve clarity and test different material combinations.

How It Works (The Science Behind It)

Each layer in the filtration system removes different types of impurities. Gravel catches large debris, sand filters out smaller particles, and activated charcoal helps absorb chemicals and odors. This process simulates how natural filters (like soil and rock layers) clean groundwater, as well as how treatment plants purify drinking water.

STEM Concepts Involved:

• Water cycle and conservation
• Filtration and separation techniques
• Environmental engineering
• Problem-solving and critical thinking

Air Quality Test

The air quality test is a simple, effective way to help kids observe and understand air pollution in their local environment. By creating basic air pollution monitors, students can visually see how much particulate matter is present in the air. This activity raises awareness about air pollution sources and encourages discussions on ways to reduce it, making it an ideal Earth Day project.

Materials Needed:

• White index cards or stiff white paper
• Petroleum jelly (or shortening)
• String or tape
• Magnifying glass (optional)
• Marker

Steps:

1. Use a marker to divide the index card into sections and label each section with the location where it will be placed.
2. Coat one side of the index card lightly with petroleum jelly.
3. Use string or tape to hang the cards in various outdoor locations (e.g., near a road, playground, or garden).
4. Leave the cards outside for 24 to 48 hours.
5. Collect the cards and examine them, using a magnifying glass to observe the particles stuck to the jelly.
6. Compare the cards from different locations and record your observations.

Be warned – you may be surprised what you find!

How It Works (The Science Behind It)

The petroleum jelly traps airborne particles such as dust, pollen, soot, and pollutants. By examining the collected debris, students can see how much particulate matter is present in the air at different locations. This provides a visual understanding of air quality and pollution levels.

STEM Concepts Involved:

• Environmental science (air pollution)
• Observation and data collection
• Human impact on ecosystems
• Scientific inquiry and analysis

Earth Day Eruption: Mini Eco Volcano

Description:
Celebrate Earth Day by creating a mini eco-friendly volcano! This version uses natural colors and encourages kids to think about the Earth and its processes while enjoying an exciting foamy reaction. Perfect for combining environmental awareness with hands-on science.

Materials Needed:

• Baking soda (about 2 tablespoons)
• Vinegar (about ½ cup)
• Small cup or container (or create a “volcano” shape using natural materials like sand or dirt)
• Natural food coloring (green and blue for an Earth theme)
• Dish soap (optional, for frothier bubbles)
• Tray or large pan (to catch the overflow)
• Small pebbles, leaves, or flowers for decoration (optional)
• Spoon for stirring

Steps:

1. Build your volcano: Place a cup or container on the tray, or mound up sand or dirt around it to create a natural-looking volcano. Decorate the mound with pebbles, leaves, or small flowers for an Earth-themed touch.
2. Add baking soda: Scoop about 2 tablespoons of baking soda into the container at the center of your volcano.
3. Color it naturally: Add a few drops of natural green or blue food coloring to the baking soda. If you want a frothier eruption, add a small squirt of dish soap.
4. Pour in the vinegar: Slowly pour vinegar into the container. Watch as the green and blue foam erupts like a mini natural geyser.
5. Observe and discuss: Use this opportunity to talk about natural Earth processes like volcanic eruptions and how they shape our planet.

How It Works (The Science Behind the Eruption):
The eruption is caused by a chemical reaction between vinegar (an acid) and baking soda (a base). This reaction produces carbon dioxide gas, which forms bubbles and causes the foamy overflow. The addition of dish soap traps the gas in bubbles, creating a frothier effect. Using natural decorations and colors aligns the activity with the Earth Day theme.

STEM Concepts Involved:

• Chemistry: Understand acid-base reactions and gas production.
• Earth Science: Learn about how volcanic eruptions contribute to shaping the Earth’s surface.
• Environmental Awareness: Discuss the importance of Earth Day and the role of natural processes in maintaining a healthy planet.
• Scientific Method: Experiment with different amounts of vinegar, baking soda, or dish soap to explore the effects on the reaction.
• Creativity and Design: Create a volcano using natural materials to connect science with the Earth Day theme.

Earth Day Crystal Growth Experiment

Description:

Celebrate Earth Day by growing crystals on pipe cleaners shaped like Earth, trees, or recycling symbols! This activity encourages kids to think about science and sustainability while creating sparkling, eco-inspired designs.

Materials:

• Green, blue, and brown pipe cleaners
• Borax powder (or salt/sugar as alternatives)
• Boiling water
• Glass jars or clear plastic cups
• Spoons for stirring
• String or thread
• Pencils or sticks (to suspend the pipe cleaners)
• Food coloring (green, blue, or brown)
• Scissors
• Optional: Small Earth stickers or eco-themed decorations

Steps:

1. Shape the Pipe Cleaners: Bend pipe cleaners into Earth Day-themed designs, such as globes, trees, recycling symbols, or leaves.
2. Prepare the Solution: Boil water and carefully pour it into the jars. Add borax powder (1 tablespoon per cup of water) and stir until fully dissolved, creating a supersaturated solution. Add green, blue, or brown food coloring to match the theme.
3. Suspend the Shapes: Tie the pipe cleaner designs to a pencil with string and balance the pencil across the jar, ensuring the shapes are submerged without touching the sides.
4. Wait and Observe: Place the jars in a safe, undisturbed area. Over 12–24 hours, observe the crystal formation.
5. Remove and Dry: Once the shapes are covered in crystals, carefully remove them and let them dry. Attach small Earth stickers or other eco-themed decorations if desired.

How It Works:

This experiment demonstrates crystallization, where borax particles in a supersaturated solution settle on the pipe cleaners as the water cools. These particles arrange themselves into intricate, solid crystal structures.

STEM Concepts:

• Chemistry: Explore solubility, saturation, and the crystallization process.
• Physics: Understand how crystals form and grow in a lattice structure.
• Art and Design: Incorporate creativity by shaping pipe cleaners into eco-themed designs and choosing Earth-inspired colors.
• Scientific Method: Practice hypothesizing, observing crystal growth, and recording findings.
• Sustainability Message: Discuss how understanding natural processes like crystallization can inspire eco-friendly innovations.

This Earth Day activity merges creativity and science, inspiring kids to appreciate the wonders of our planet!

Earth Day Balloon Rocket

Celebrate our beautiful planet by launching a rocket that reminds everyone about the importance of caring for Earth! Decorate your balloon with Earth Day designs—think globes, trees, or recycling symbols—and watch it zoom along a string. This fun experiment demonstrates propulsion and Newton’s Third Law of Motion in a memorable, eco-themed way.

Materials Needed

• Balloon (preferably green, blue, or Earth-themed)
• Long piece of string (6–10 feet or more)
• Drinking straw (or small tube)
• Tape
• Two chairs (or other supports to hold the string tight)
• Markers, stickers, or cutouts (Earth Day-themed: trees, recycling symbols, etc.)

Steps

1. Decorate the Balloon
   • Add Earth-friendly designs: the planet Earth, trees, flowers, or recycling logos.
   • Write a short Earth Day message like “Protect Our Planet” or “Go Green!”
   • Leave room near the balloon’s neck for attaching the straw.
2. Set Up the String
   • Tie one end of the string to a chair (or another support).
   • Thread the free end of the string through the straw, then tie it to the second chair.
   • Make sure the string is stretched tight.
3. Attach the Balloon
   • Inflate your Earth Day balloon but do not tie it—pinch the neck to keep air inside.
   • Use tape to secure the balloon to the straw, positioning the neck so it faces the starting chair.
4. Launch Your Earth Rocket
   • Release the balloon’s neck and watch it fly along the string!
   • Celebrate Earth Day by thinking about how we can harness energy in ways that respect the planet.
5. Experiment With Variations
   • Adjust the angle of the string—see how the balloon’s path changes if the string is slanted up or down.
   • Try using different balloon shapes or sizes.
   • Note how each variation affects the speed, distance, or direction of the balloon rocket.

How It Works

When you release the balloon’s neck, the escaping air pushes back against the balloon, causing it to move forward. This illustrates Newton’s Third Law of Motion—for every action, there is an equal and opposite reaction. The string-and-straw setup guides the balloon and reduces friction, allowing it to glide smoothly.

STEM Concepts

• Newton’s Third Law of Motion: Explores action and reaction forces.
• Propulsion: Shows how thrust is generated when air (or any gas) escapes from a container.
• Force & Motion: Demonstrates how forces cause objects to accelerate in a particular direction.
• Friction Reduction: Highlights how the straw on a taut string helps the balloon travel smoothly.

This Earth Day, combine science learning with environmental awareness—let your balloon rocket remind everyone that we can keep our planet moving forward by protecting it!

Dancing Earth Day Orbs Experiment

Celebrate Earth Day with a fun and educational experiment! Use small blue and green objects (to represent the Earth, like marbles or painted ping pong balls) or lightweight natural materials like small acorns or seeds to create a bubbling, dancing display in a carbonated drink. This activity is a great way to explore the concepts of buoyancy and gas properties while discussing the importance of protecting our planet.

Materials Needed

• Clear carbonated beverage (e.g., club soda, sparkling water, or lemon-lime soda)
• Transparent glass or clear cup
• Small blue and green objects (e.g., mini marbles, painted ping pong balls, or lightweight, Earth-themed decorations)
  (Optional: Use lightweight natural materials like acorns, seeds, or small leaves to tie into an Earth Day theme.)

(Optional variation: Replace the carbonated beverage with a mixture of water, vinegar, and baking soda to generate bubbles.)

Steps

1. Fill the Glass: Pour the carbonated beverage into a transparent glass until it’s about three-quarters full.
2. Add the Earth Day Orbs: Gently place your blue and green objects (or natural items) into the liquid.
3. Observe the Motion: Watch as the objects sink, rise, and fall in a “dancing” motion as the bubbles attach, lift them up, and then pop at the surface.

(Tip: If the objects stop dancing, gently stir the liquid or refresh your carbonated beverage.)

How It Works

• Objects Sink First: Earth-themed objects (or natural items) are initially denser than the liquid, so they sink to the bottom.
• Bubble Lift: Carbon dioxide bubbles in the drink cling to the surface of the objects. As more bubbles attach, they reduce the objects’ density, causing them to rise.
• Pop & Drop: When the objects reach the surface, the bubbles pop, and the objects sink again, ready for the cycle to repeat.

STEM Concepts

• Density & Buoyancy: Understand how objects can float or sink depending on their density and the effect of attached gas bubbles.
• Properties of Gases: Learn how carbon dioxide bubbles form, attach to objects, and affect their movement.
• Chemical Reactions (if using baking soda and vinegar): Explore how reactions produce carbon dioxide for the dancing effect.
• Environmental Awareness: Discuss how observing natural materials in science experiments connects us to the importance of sustainability and protecting Earth’s resources.
• Observation & Inquiry: Encourage kids to predict, observe, and explain the motion, fostering curiosity and scientific thinking.

DIY Earth Day Slime

Celebrate Earth Day by making eco-inspired slime! This activity uses Earth-themed colors and sparkly accents to resemble our beautiful planet while teaching kids about polymers and sustainability.

Materials Needed

• White school glue (about ½ cup)
• Liquid starch (about ¼ cup) OR a borax solution (1 teaspoon borax dissolved in 1 cup warm water)
• Blue and green food coloring
• Eco-friendly glitter (optional)
• Mixing bowl
• Spoon or stir stick
• Measuring cups

Steps

1. Divide the glue: Split the glue into two bowls, approximately ¼ cup in each.
2. Color the glue: Add blue food coloring to one bowl and green food coloring to the other. Stir each until evenly colored.
3. Mix in glitter: If desired, add eco-friendly glitter to each bowl for a sparkly effect.
4. Combine with activator:
   • For each bowl, slowly add about ⅛ cup of liquid starch or borax solution while stirring.
   • Mix until the slime forms and pulls away from the sides of the bowls.
5. Knead each slime batch until smooth and stretchy.
6. Combine the colors: Twist and fold the blue and green slime together gently to resemble Earth. Be careful not to overmix to keep the distinct colors visible. (Yeah, we overmixed! Kids will be kids.)

How It Works
This Earth Day slime is a polymer made by linking glue molecules into stretchy chains with an activator. The colors and glitter help celebrate Earth’s beauty while connecting science and environmental awareness. To learn more about the science behind slime, read our article on The Science of Slime.

STEM Concepts

• Chemistry: Understand the chemical reaction that creates polymers.
• Art and Science Fusion: Explore creativity with Earth-themed colors and designs.
• Measurement and Ratios: Practice accurate measurements to achieve the best slime consistency.
• Environmental Awareness: Discuss sustainability and the importance of using eco-friendly materials.

Tip: Store your Earth Day slime in a reusable container and use the opportunity to talk about reducing single-use plastics and protecting our planet!

Balloon Inflation

Celebrate our planet with an Earth-friendly take on the classic vinegar and baking soda balloon experiment! By reusing or upcycling a plastic bottle and using green or Earth-themed balloons, you’ll see how the chemical reaction creates carbon dioxide gas (CO₂)—a greenhouse gas—while reminding us of the importance of caring for our environment.

Materials Needed

• Reusable plastic or glass bottle (try to reuse something you already have)
• Green or Earth-themed balloon (balloon with Earth designs or green/blue colors)
• Vinegar (about ¼ to ½ cup)
• Baking soda (about 1–2 tablespoons)
• Food coloring (optional; green or blue for Earth Day spirit)
• Funnel (optional but helpful)
• Measuring spoons and measuring cup

Steps

1. Give It an Earthy Look
   • (Optional) Add a few drops of green or blue food coloring to the vinegar to represent the Earth’s land and oceans.
2. Measure the Vinegar
   • Pour about ¼ to ½ cup of vinegar into your reusable bottle using a measuring cup.
3. Load the Baking Soda
   • Using a funnel or spoon, carefully place 1–2 tablespoons of baking soda into your Earth-themed balloon.
4. Attach the Balloon
   • Stretch the balloon’s opening over the mouth of the bottle, ensuring it’s snug. Keep the balloon to the side so the baking soda stays inside for now.
5. Start the Reaction
   • Tilt the balloon upward so the baking soda falls into the colored vinegar.
   • Observe the fizzing foam that forms as carbon dioxide is released and inflates the balloon.
6. Eco-Friendly Tips
   • Rinse and reuse your bottle for future experiments or daily use.
   • Properly dispose of any leftover materials to keep our planet clean.

How It Works

When baking soda (a base) combines with vinegar (an acid), they react and form carbon dioxide gas (CO₂) among other products. This gas bubbles up and inflates the balloon. Because CO₂ is a greenhouse gas that affects our atmosphere, Earth Day is a perfect time to learn about it and think about ways we can help reduce our carbon footprint.

STEM Concepts Involved

• Chemistry: Observing an acid-base reaction that generates carbon dioxide gas.
• Physics: Understanding how gas expands and inflates the balloon under pressure.
• Environmental Science: Making connections between CO₂ and its role in Earth’s atmosphere.
• Upcycling & Sustainability: Reusing materials (like a plastic bottle) and properly disposing of waste to protect our planet.

Earth Day Science Activities Wrap-Up:

This Earth Day, you’ve shown how science can help us appreciate and protect our planet. From creating beautiful crystal formations to experimenting with natural materials, these activities teach kids to think creatively and care for the environment.

By exploring and discovering, they’re learning valuable skills while building a deeper connection to the Earth. Keep the spirit of curiosity and conservation alive, and remember—every day is a chance to celebrate and care for our planet. Happy experimenting, and happy Earth Day!