From this part of the USGS site, scroll down to find the map of the world that shows current earthquake activity. Run your cursor over the hot spots on the map to see the actual location of the quake and then click on the spots to find out further information. Visit the crust, the mantle, and the core of the earth. The crust is the thin outer layer which is kind of like the skin of the earth. On the average, the crust is only about 6 miles thick.
Continental crust is older and thicker than oceanic crust.
The mantle right below the crust is about 1800 miles thick and is made of extremely hot rock that is mostly melted and bubbles around like really thick molasses. The mantle has 3 layers. The core is even hotter. It is made of metal and is thought to be liquid on the outside and solid inside. Virtually travel to Mars and check out Olympus Mons which is the highest volcano in the solar system.