Third Grade STEM Activities for Kids (223 results)

STEM Activity

141 reviews

Use crayons to model the rock cycle in this fun activity! You will make colorful sedimentary, metamorphic, and igneous "rocks" from crayon shavings. Read more

Suck It Up! How Water Moves Through Plants

STEM Activity

113 reviews

Have you ever heard someone say, "That plant is thirsty," or, "Give that plant a drink of water"? We know that all plants need water to survive, even bouquets of cut flowers and plants living in deserts. But have you ever thought about how the water moves within the plant? In this activity, you will put carnations in dyed water to figure out where the water goes. Where do you think the dyed water will travel, and what will this tell you about how the water moves in the cut flowers? Read more

Homemade Slushies

STEM Activity

106 reviews

Do you enjoy ice-cold drinks? A slushy is about as close as you can get to liquid ice: colder than water, but more drinkable than ice! Using some common household items, a little bit of patience, and the help of science, you can make this delicious, sweet drink at home. Try the activity, and you will be rewarded with a delightful treat! Read more

Featured

Make String from Algae

STEM Activity

210 reviews

Did you know that the seaweed you've seen in the ocean or even eaten as a snack is inspiring innovators to imagine new materials? Large brown algae, like kelp, contains polymers—long chains of molecules—that are more environmentally friendly than the ones in most plastics. These natural polymers (alginates) could eventually be used to create sustainable everyday objects. Try your hand at using a bit of chemistry to turn biodegradable polymers from algae into your own custom… Read more

How to Grow the Best Crystals

STEM Activity

128 reviews

Have you ever wondered how crystals are made? Crystals come in all different shapes and sizes. However, the purest and cleanest crystals are usually also the ones that grow to be the largest in size. In this activity, you will compare the size and shape of crystals grown at different temperatures. With just water and Borax, a household cleaning product, you can discover the method for growing large, pure crystals! Read more

Build a Bird Nest

STEM Activity

68 reviews

Different types of birds lay their eggs in different places. Some build tiny nests in bushes, some build enormous nests in tall trees. Some lay their eggs directly on the ground or on rocky ledges. Those that build nests use many different types of materials. In this project you will try to build your own bird nest using only natural materials that you can find outside. Can you do better than a bird? Read more

Build a Solar Updraft Tower

STEM Activity

201 reviews

Have you ever had a sunburn? If so, you know how powerful the Sun's heat can be! Did you know that this heat can also be turned into electrical energy? You may have heard about solar cells, but what about a solar updraft tower? This very simple structure uses the sun to heat up air, which then powers a turbine within a large tower. In this activity, you will build one of these towers yourself. Do you think you can make a propeller spin with just hot air? Read more

Color-changing Cabbage Chemistry

STEM Activity

58 reviews

What if you could take a single liquid, and change it into a rainbow of colors without using food dye. You can! In this activity you will use red cabbage to make what is called an indicator solution. Indicator solutions can change colors depending on what you add to them. In this case adding something acidic (like lemon juice) will change it to one color while adding something basic (like bleach) will change it to another. Try and see how many colors you can make using different household… Read more

Exploring Enzymes

STEM Activity

126 reviews

Have you ever wondered how all the food that you eat gets digested? It is not only the acid in your stomach that breaks down your food—many little molecules in your body, called enzymes, help with that too. Enzymes are special types of proteins that speed up chemical reactions, such as the digestion of food in your stomach. In fact, there are thousands of different enzymes in your body that work around-the-clock to keep you healthy and active. In this science activity you will investigate… Read more

Hydroponics Made Easy

STEM Activity

137 reviews

Do you think plants can grow without soil? If you've tried growing vegetables, you probably planted the seeds or seedlings in soil. Soil gives the plants the nutrients they need to grow. However, plants can grow without soil, too, using a process called hydroponics. In this activity, you will transform a bottle into a mini-garden that needs only light, air, and nutrient-rich water to grow! Read more

Investigate Alien Genetics

STEM Activity

123 reviews

Have you ever wondered why biological siblings look so much alike? Why do they often share physical traits, such as hair color or eye color? It all has to do with their genes. Genes are passed on from parents to their offspring. This means that you share some of the same genes with your biological parents and siblings! In this activity, you will use an alien model to demonstrate how genes or physical traits are passed on from parents to their offspring. How similar will your alien siblings look? Read more

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