What are the three states of matter kids learn about?

Everything around us, from the air we breathe to the chair we sit on, is made of something called matter. Matter is anything that has mass and takes up space. Scientists have observed that matter usually exists in different forms, or states, depending on how its tiny particles are arranged and move. For young learners, the three most common and easily observable states of matter are solid, liquid, and gas.

Imagine tiny building blocks that make up everything. In a solid, these blocks are packed very tightly together and can only vibrate in place. This is why a solid, like a rock or a block of ice, keeps its own shape and volume. It doesn't spread out or change its form easily. You can pick up a solid and it will stay just as it is.

Now picture those same tiny blocks, but with a little more room to wiggle. In a liquid, the particles are still close, but they can slide past one another. This allows liquids, like water or juice, to flow and take the shape of whatever container they are in, while still keeping the same amount or volume. If you pour juice from a carton into a glass, it changes shape to fit the glass.

Finally, consider those blocks moving very far apart and zooming around freely. This is what happens in a gas. The particles in a gas are spread out and move in all directions, so a gas doesn't have a definite shape or volume. It will expand to fill any container it's in, or float around freely if it's not contained. Think of the air around you or the steam rising from a hot drink; these are examples of gases. Interestingly, matter can often change from one state to another, like how ice (a solid) melts into water (a liquid) and then can turn into steam (a gas) when heated.