The theory of plate tectonics states that the Earth’s lithosphere is broken into 15 major plates and that move on the top of the hot plastic upper mantle, known as the asthenosphere. This theory also says that these plates are in motion as a result of convection in the asthenosphere, creating a variety of interactions at the plate boundaries. At the plate boundaries, plates may converge (collide), diverge (separate), or slide past each other (transform boundary). In addition, some plates may appear to be inactive. The purpose of this lab is to demonstrate the different types of interactions at plate boundaries.
Materials
graham crackers
Rice Krispy treat
Frosting/Marshmallow Fluff
water
plastic spoon
paper plate
Procedure
Part 1: Divergent Plate Boundaries
Part 2: Convergent Plate Boundaries (Continental and Oceanic)
Part 3: Convergent Plate Boundaries (Continental)
Part 4: Transform Plate Boundaries
Watch the video below before following the procedure for each plate boundary. You will be given permission to enjoy your tectonic plates with your partner only after Ms. Shon has signed your station packet. Have fun!

Procedure:
1. Divide your plate into four sections with a pencil/pen (see picture on the right)
2. Take two graham cracker pieces.
3. Using the spoon, spread a thick layer of frosting in one quarter of your paper plate. It should be about the size of both graham crackers, and about equally thick.
4. Lay the two pieces of graham cracker side by side on top of the frosting so they are touching.
5. To imitate the result of diverging oceanic plates, press down on the crackers as you slowly push down and apart in opposite directions.

Procedure:
1. Take one new graham cracker. This represents the thin but dense oceanic plate.
2. Spread a thin layer of frosting on another quarter of your paper plate.
3. Take one Rice Krispy treat and lay it next to the graham cracker so they are almost touching, end to end. The Rice Krispy treat represents the thicker but less dense continental plate.
4. Push the two “plates” slowly toward each other and observe which plate rides up over the other. On the actual surface of the Earth, the oceanic plate is subducted.

Procedure:
1. Take two new graham crackers. Each piece of graham cracker represents a continental plate.
2. Spread a thin layer of frosting on another quarter of your paper plate.
3. Dip one end of each of the two graham crackers into a cup of water. See picture.
4. Immediately remove the crackers and lay them end to end on the frosting with the wet edges nearly touching.
5. Slowly push the two crackers together.

Procedure:
1. Take two graham cracker pieces.
2. Spread a thick layer of frosting on the last quarter of your plate.
3. Lay the two pieces of graham cracker side by side on top of the frosting so they are touching.
4. Place one hand on each of the graham cracker pieces and push them together by applying steady, moderate pressure. At the same time, also push one of the pieces away from you while pulling the other toward you. If you do this correctly, the cracker should hold while you increase the push-pull pressure, but will finally break from the opposite forces.