It’s never too early to start building a strong science vocabulary! Whether you’re a teacher, homeschool parent, or just raising a curious kid, this list of science terms will help young learners talk and think like scientists. With over 60 kid-friendly science vocabulary words and easy-to-understand definitions, it’s the perfect resource to support any science lesson or experiment.
How to Use These Science Vocabulary Words
Science vocabulary isn’t just for flashcards or tests—it’s meant to be used! Introduce 1–3 new words during each hands-on experiment or activity. Let kids write them in a journal, use them in a sentence, or sketch a drawing. The more ways kids interact with the words, the more they stick.
🔎 TIP: Many of the science vocabulary words below are linked to related experiments you can try. Click on a word to explore the science behind it in action!
Science Vocabulary Words by Category
Matter & Materials
💡Explore the building blocks of everything around us! These words help kids understand the states of matter, how materials mix and behave, and how substances can be grouped and measured.
Atom: The smallest part of an element. Everything is made of atoms.
Molecule: A group of atoms joined together. Water is a molecule made of hydrogen and oxygen.
Matter: Anything that takes up space and has mass.
Solid: A state of matter with tightly packed particles. Keeps its shape.
Liquid: A state of matter with loosely packed particles. Takes the shape of its container.
Gas: A state of matter with particles that spread out. Can fill any space.
Polymer: A material made of long chains of molecules. Slime and plastic are polymers.
Mixture: Two or more substances combined without a chemical reaction. You can separate them.
Solution: A mixture where one substance dissolves into another.
Dissolve: When a substance mixes evenly into a liquid.
Emulsification: Combining two liquids that don’t usually mix, like oil and water.
Density: The compactness of stuff in space or the amount of material that is in a set size.
Viscosity: How thick a liquid is. Honey is more viscous than water.
Energy & Forces
💡These words explain how things move, why they stop, and what forces are at work in our everyday lives. Perfect for understanding motion and mechanics!
Kinetic Energy: Energy an object has when it’s moving.
Potential Energy: Stored energy. A stretched rubber band has potential energy.
Gravity: A force that pulls things toward each other. Earth’s gravity pulls us down.
Friction: A force that slows or stops objects that rub together.
Buoyancy: The ability of an object to float in a liquid.
Surface Tension: A “skin” on the surface of water that helps things float.
Lever: A simple machine that helps move things with a pivot point called a fulcrum.
Rest: When something is not moving. The opposite of motion.
Motion: A change in an object’s position.
Scientific Process
💡 Science is all about asking questions and finding answers! These words help kids learn how to explore, experiment, and observe like real scientists.
Hypothesis: A testable idea or prediction.
Experiment: A test to learn something or solve a problem.
Observation: Using your senses or tools to notice and record what’s happening.
Data: Information collected during an experiment.
Variable: Something you can change or measure in an experiment.
Prediction: A guess about what will happen based on what you know.
Chemistry & Reactions
💡 These words help kids understand the makeup of substances and what happens when materials change or react. Chemistry is all around us—in cooking, cleaning, and even breathing!
Acid: A substance with a sour taste and low pH (like lemon juice).
Base: A substance that feels slippery and has a high pH (like baking soda).
pH Scale: A scale from 0 to 14 that shows how acidic or basic something is.
Chemical Reaction: When substances change to make something new. Like baking a cake.
Life Science & Environment
💡 From the air we breathe to the food we eat, these terms help kids explore the living world, the environment, and how our bodies and ecosystems function.
Carbon Dioxide: A gas made by living things and used by plants.
Nitrogen: A gas in the air that helps plants grow. Also in proteins and DNA.
Protein: A nutrient made of amino acids. Helps build muscles and other body parts.
Fats: Nutrients that store energy. Found in oils and meat.
Minerals: Natural solid substances that aren’t from living things.
Physics & More
💡 These physical science words cover how objects interact with each other and the natural world. Great for exploring forces, movement, and everyday phenomena!
Magnet: An object that can pull certain metals toward it.
Mass: The amount of matter in something.
Float: When an object stays on top of a liquid.
Sink: When an object goes below the surface of a liquid.
Capillary Action: When water moves through narrow spaces, like in plants.
Cohesion: When molecules stick to each other (like water droplets).
Stratification: Grouping things into layers or categories.
Non-Newtonian Fluid: A liquid that changes thickness when squeezed or moved (like slime).
Printable Science Vocabulary List
👉 Click here to download your printable Science Vocabulary Word List
Use it in your classroom, homeschool journal, or science station!
Science Practices for Kids
Support kids in thinking like real scientists with these 8 science and engineering practices:
- Ask questions
- Build models
- Plan and carry out investigations
- Analyze and interpret data
- Use math and computational thinking
- Explain based on evidence
- Evaluate and revise
- Communicate information
These practices help kids become better problem solvers, observers, and explorers.
Best Science Books for Kids
Books are a great way to introduce new science words! Try these:
What Is a Scientist?
Learn about different types of scientists and how they explore the world around them. Read: What Is a Scientist
Fun Experiments to Use These Words
- Lemon Volcano → Use: acid, chemical reaction
- Lava Lamp → Use: density, molecule, buoyancy
- Balloon Experiment → Use: gas, pressure, motion
- Slime → Use: polymer, viscosity, non-Newtonian fluid
FAQ: Science Vocabulary for Kids
Q: What is science vocabulary?
A: Science vocabulary includes key terms that help kids understand and describe science concepts.
Q: How can I help my kids learn science terms?
A: Use the words during fun experiments, read science books, and play vocabulary games.
Q: What are good beginner science words?
A: Start with words like solid, liquid, gas, float, sink, and observe.
Q: Is there a printable list?
A: Yes! Download our printable science vocabulary list for easy reference.
Q: Are there science experiments for these vocabulary words?
A: Yes! Many words in the list link directly to experiments so kids can explore the concepts in action.
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