Students use graham crackers and frosting to learn about the different aspects of plate tectonics. They manipulate the graham crackers in various ways to model divergent plate boundaries, convergent plate boundaries - continental and oceanic, convergent plate boundaries - continental, and lateral plate boundaries. Students observe what happens to the graham crackers and frosting and discuss their findings.
Below is a description of the activity from http://www.mbmg.mtech.edu/kids/shakin.htm
A crack in the
earth's crust is called a fault. The large crack where two huge earth
plates move against each other is a fault line. Fault lines are where the
Put two graham crackers side by side, and slide one up away from you and the other one down toward you.
When plates move past each other like this, things don't exactly go smoothly. In fact, the plates usually get stuck on each other and then give a lurch and move on, sending waves of vibrations through the earth's interior (much like the circular waves that ripple out when you drop a pebble in the water). These vibrations are so powerful the we have a special name for themó earthquake!
Whose fault is this?
Put two graham
crackers very close to each other on the wax paper and slowly push them
You've made a rift, or big crack in the ocean floor. As the plates separate, magma oozes up from below and makes new ocean floor or creates underwater mountain ranges.
two crackers toward each other, make one slide underneath the other.
When this happens on earth, watch out! The bottom plate starts to melt from the intense heat and pressure. It becomes new magma that floats up between two plates, building up and up over many years until it finally causes a volcano blast! That plate action caused Mt. St. Helens in Washington State to blow its top!
two graham crackers side by side on the wax paper (wet the edge of one
graham cracker in milk first), and slowly push them together.
The ridge of pushed -up cracker is just like many mountain ranges around the earth that were formed as two plates slowly crumbled together over millions of years. The Himalayas ( the mountain range that includes Mount Everest) were formed when India crashed into Asia.
A similar, but more complete, lesson is given in Windows to the Universe. The materials needed are:
For each student:
|One large graham crackers broken in half (i.e., two square graham crackers)|
|Two 3-inch squares (approx.) of fruit roll up|
|Cup of water|
|About one square foot of wax paper with a large dollop of frosting. ( Instruct students to spread frosting into a layer about half a cm thick.)|
|Plastic knife or spoon|
Directions overheads: http://www.windows.ucar.edu/tour/link=/teacher_resources/snack_tect_overheads.html