Science does not need to feel stressful. You do not need a fancy lab or a classroom cart stacked with gadgets. Most of the best STEM moments happen with simple materials you already have around the house. I have seen kids learn more from baking soda and vinegar than from half the expensive kits parents buy at the store.
This guide pulls together experiments that actually work and do not turn your kitchen into a disaster zone. I have taught STEM for more than 15 years, and I have run these activities with real kids who get curious, distracted, excited, nervous, silly, chaotic, and brilliant all in the same afternoon. If you need a place to start, this list will help you get moving fast.
1. Magic Milk Experiment
This one hits hard every time. Kids watch colors explode across the surface of milk when soap breaks the surface tension. It teaches chemistry basics without feeling like a lecture.
Materials: milk, dish soap, food coloring, cotton swab.
Concepts: surface tension, molecules, chemical reactions.
2. Baking Soda Volcano
Yes, it is basic. Yes, it still works. Every single kid still cheers. It is a reliable introduction to reactions and gas formation.
Materials: baking soda, vinegar, dish soap, cup.
Concepts: acids, bases, carbon dioxide.
3. Static Balloon Hair Lift
Kids rub a balloon on their hair and suddenly feel like powerful wizards. It never gets old. It also helps them see electrons in action.
Materials: balloon.
Concepts: static electricity.
4. Walking Water Rainbow
Colored water slowly climbs paper towels and mixes into new colors. This one works even better if you film it as a time lapse.
Materials: cups, water, paper towels, food coloring.
Concepts: capillary action, absorption.
5. Salt Crystal Garden
Kids mix salt water and let it evaporate to create beautiful crystals. It feels like magic, but it is all chemistry.
Materials: salt, water, small containers.
Concepts: evaporation, crystallization.
6. Balloon Rocket
Thread, a straw, and a balloon can turn a hallway into a launch track. Kids learn fast how air pressure creates movement.
Materials: string, straw, balloon, tape.
Concepts: force, pressure, Newton’s laws.
7. Oobleck
It looks like slime, feels like slime, but behaves like a weird half-solid, half-liquid thing that makes kids question everything.
Materials: cornstarch, water.
Concepts: non-Newtonian fluids.
8. Paper Airplane Distance Test
Kids build planes, test them, record distances, and change one variable at a time. It becomes a real experiment fast.
Materials: paper, tape measure.
Concepts: aerodynamics, variables.
9. DIY Lava Lamp
Oil, water, and fizz tablets create an eye-catching tower of rising bubbles. It shows density differences in a visual way.
Materials: clear cup, oil, water, food coloring, antacid tablet.
Concepts: density, gas release.
10. The Egg Drop Challenge
Let kids build a container that protects an egg from a fall. It is engineering in its simplest form.
Materials: anything soft or protective.
Concepts: force, design, problem solving.
11. Fizzy Snow Dough
A winter-themed reaction that combines sensory play with basic chemistry. Kids love the texture and the fizz.
Materials: baking soda, water, vinegar.
Concepts: reactions, states of matter.
12. Rubber Egg Experiment
Vinegar dissolves the shell and leaves behind a bouncy membrane. Kids get amazed and slightly terrified.
Materials: egg, vinegar, jar.
Concepts: osmosis, chemical reactions.
13. Mentos + Soda Test
Classic, chaotic, always outside. Kids test different sodas and learn why some explode higher than others.
Materials: soda bottles, Mentos.
Concepts: nucleation, gas release.
14. Homemade Compass
Float a magnetized needle on water and kids see how Earth’s magnetic field works.
Materials: needle, magnet, bowl of water, cork.
Concepts: magnetism, navigation.
15. Shadow Length Measurement
Kids track shadows every hour to see how the sun moves across the sky.
Materials: stick, tape measure, chalk.
Concepts: rotation, solar position.
16. Soap-Powered Boat
A drop of dish soap propels a cardboard boat across a tray of water. Kids feel like geniuses.
Materials: cardboard, water, dish soap.
Concepts: surface tension.
17. Straw Bridges
Tape + straws + imagination equals surprisingly strong structures. Kids quickly learn how triangles create strength.
Materials: straws, tape.
Concepts: engineering, stability.
18. Rainbow Density Column
Layer different liquids to form a colorful stack. It looks advanced but is actually easy.
Materials: honey, dish soap, water, oil.
Concepts: density, buoyancy.
19. Ice Excavation Dig
Freeze toys in ice and let kids rescue them using warm water and tools. It becomes a mini archaeology dig.
Materials: toys, water, freezer.
Concepts: melting, states of matter.
20. Marble Run Engineering
Build tracks from cardboard tubes and test how to make marbles go faster.
Materials: toilet paper tubes, tape.
Concepts: gravity, friction.
21. DIY Stethoscope
Kids make a simple listening device and explore how sound travels.
Materials: funnel, tubing, plastic wrap.
Concepts: sound waves, vibration.
22. Coin Battery
Kids power a small LED with stacked coins and vinegar-soaked paper. It feels like real engineering.
Materials: coins, paper towels, vinegar, LED.
Concepts: electricity, circuits.
23. Magic Pepper Trick
Sprinkle pepper on water and tap it with soapy fingers. Pepper darts away fast. Kids usually gasp.
Materials: pepper, soap, water.
Concepts: surface tension.
24. DIY Slime
Kids experiment with different ratios to see what creates stretchy slime versus thick slime.
Materials: glue, baking soda, contact solution.
Concepts: polymers.
25. DIY Parachutes
Kids build parachutes and test which shapes fall slowest. Great for indoor or outdoor testing.
Materials: plastic bags, string, small toy.
Concepts: air resistance.
26–50. Quick STEM Activities That Always Work
To keep this guide focused and not overly scroll-happy, here is a clean list of additional activities. These are all reliable, repeatable, and classroom friendly.
- Paper towel chromatography
- Balloon-powered car
- Simple electric motor
- Earthquake shake table
- Tin foil boats
- Floating paper clip
- Homemade thermometer
- Rain cloud in a jar
- DIY magnifying glass
- Seed sprouting jar
- Solar oven with a pizza box
- Straw pan flute
- Vinegar + steel wool reaction
- Water xylophone
- Recycled bottle terrarium
- Forces of motion bowling
- Rain gauge
- Magnetic slime
- Erupting lemon experiment
- Balloon barometer
- Alka seltzer rockets
- Center of mass balancing demo
- DIY kaleidoscope
- Color changing cabbage juice
- Paper helicopter blades
How to Run STEM Activities Without Stress
Running experiments does not need to feel chaotic. Here are the rules I use in my classroom.
Keep materials simple. Kids focus better when you remove clutter.
Explain the why. Even one sentence helps kids connect ideas.
Let them mess up. Most real science happens in the mistakes.
Ask questions instead of giving answers. It builds confidence.
Celebrate tiny wins. STEM grows with encouragement.