PROBLEM: Why do earthquakes cause damage?

PREDICTION:

MATERIALS: margarine tubs, teaspoons, oil, water, aluminum foil.

PROCEDURE: Fill the margarine tubs 1/2 full of water

1. Gently tap the sides of the tub. What are you creating in the tub?
     
2. Tap the sides a little harder. Does the pattern change? How?
     
3. Float a flattened piece of foil in the tub. Tap gently. What happens?
     
4. Tap a little harder on the outside. Does it still float?
     
5. With the teaspoon, tap the water directly. Can you cause the foil to sink without touching the foil and without spilling any water?
     
6. Take the foil out. Put 1 teaspoon of oil on the water. Tap the sides gently. What happens?
     
7. Tap the sides a little harder. What happens?
     
8. Fill in the blank letter in the sentence below.
   
   WHEN THE STRESSES IN THE EARTH BREAK THE CRUST THEY SEND OUT W _ _ _ _.

CONCLUSION:

What causes some of the damage during an earthquake?