Making a three-dimensional model of the Earth's interior is a creative and educational way for kids to learn about the Earth we live on. The layers that make up the Earth include the crust, outer core, inner core and mantle. Each layer is made of a different material, from granite and basalt (the crust) to a molten lava core. When designing a 3-D model, consider which approach shows the most comprehensive view of the Earth from the outside and the inside.
Using coloured clay, you can form a sphere model of the Earth. Form the clay into a sphere at least 4 or 5 inches in diameter. The larger the sphere, the easier it will be for a viewer to see all the parts of your model. You can use any combination of colours, such as blue, green, red and black. Cut a triangular slice out of one quarter of the ball. This cut opens the clay up to allow you to label the Earth's interior. Assign a colour to each layer of the Earth; for instance, the crust can be a strip of green and the mantle can be yellow. For labelling, stick a pin and piece of paper with the name of the area. Or, instead of writing "mantle" on the strip of paper, you can add small cutout numbers to your model and create a key. A viewer can see that No. 5, for example, is a representation of the Earth's core. You can add texture to the model by adding a bit of glitter or sprinkles for the rocky crust, for example.
If you want to use a lightweight material, buy a foam ball at least 5 or 6 inches in diameter to mimic the Earth. Carefully cut the ball open for your child using a plastic-protected knife. You can cut the ball in two halves, like a grapefruit, or slice out one triangle chunk to show the Earth's layers. Painting the outside of the ball blue and green with acrylic paint or kid-safe spray paints and colouring each layer of the Earth's interior a different colour will make a stunning model. Stick pins or thumbtacks in the ball with labels for the parts of the Earth.
Papier-Mache Balloon Globe
You can use papier-mache to create a 3-D model of Earth. Create a papier-mache sphere using newspaper and papier-mache paste. Blow up a balloon and tie it tight to keep the air inside. Holding the balloon still, cover the balloon with papier-mache strips. Completely coat the balloon with papier-mache. After letting the papier-mache completely dry for at least one day, pop the balloon inside with a pin. You now have a round papier-mache ball you can fill with the Earth's interior layers. You can cut the ball in half or cut out one quarter to show the interior. Filling the ball with the layers of Earth using clay is one way to go.