So far students have learned:
There are 3 types of rock:
Sedimentary rock (made up of silt, sand, dirt, pebbles, etc. Pressure squishes all these items together to make a rock of many layers)
The earth has 4 layers:
Inner core: Made up of solid nickel
Outer core: Very hot liquid, all rocks and minerals are melted
Mantle: made of up of rocks and metals. Some are so hot they are liquid.
Crust: Like the skin of the earth. Made up of rock and soil