Subjects
Explore
Play
84 lessons · 1st Grade
Solids keep their shape. Liquids take the shape of their container. Gases spread out and fill any space.
When water gets very cold, it freezes into ice. When ice gets warm, it melts back into water.
Mixing things together can make something new. Mixing blue and yellow paint makes green!
Steam rises from hot water. It is water that has turned into a gas.
Objects float or sink depending on their density—how heavy they are for their size.
Light passes through transparent materials (glass), but not through opaque materials (wood).
Water is special because it can be a solid (ice), a liquid (water), or a gas (steam).
Temperature affects matter. Heat makes ice melt, and cold makes water freeze.
Objects can be described by their properties: color, size, shape, texture, weight, and flexibility.
Cooking changes food. A raw egg is liquid, but a cooked egg is solid. That is a chemical change!
Everything around you is made of matter. Matter is anything that takes up space and has weight.
Some changes can be reversed (melting ice) and some cannot (baking a cake).
A thermometer measures temperature. The liquid inside goes up when it gets hotter!
Some materials are natural (wood, cotton, wool) and some are made by people (plastic, glass, nylon).
Different materials are good for different jobs. Glass is see-through, rubber is stretchy, and metal is strong.
A mixture can sometimes be separated. You can pick out the raisins from trail mix!
Water evaporates when it gets warm—it turns from liquid into gas. That is how puddles dry up!
Rocks are made of minerals. Different minerals make rocks look different colors and textures.
Some liquids mix together (water and juice) and some do not (oil and water).
Materials can be sorted by their properties: hard or soft, rough or smooth, bendy or stiff.
Stretchy materials like rubber bands can be pulled and they bounce back to their shape.
Magnets attract some metals like iron and steel, but not wood, plastic, or aluminum.
When you dissolve sugar in water, the sugar seems to disappear, but it is still there—taste it!
Heat moves from hot things to cold things. A cold spoon in hot soup gets warm!
Sound travels through matter. You can hear sounds through air, water, and solid walls!
Air is matter even though you cannot see it. It takes up space—blow up a balloon to prove it!
Water flows downhill because gravity pulls it. Rivers flow from mountains to the sea.
Cotton absorbs water, but plastic does not. That is why raincoats are made of plastic!
When you cut paper, you change its shape but it is still paper. That is a physical change.
Metal conducts heat well. That is why pots and pans are made of metal.
