Three Types of Tectonic Plate Boundaries  Divergent : two tectonic plates move apart.  Convergent : two tectonic plates push together.  Transform: two tectonic plates move past each other.

Subduction  The process by which an oceanic tectonic plate sinks under the continental plate into the Earth’s mantle.

Materials Required  ½ graham cracker (per pair)  Square of wax paper with frosting (per pair)  Dixie cup with water (per group of 4)  Engineering Notebooks (all students!) Please discuss with group who will retrieve which supplies.

Materials  Graham crackers represents CONTINENTIAL CRUST.  Frosting represents ASTHENOSPERE.

Procedure 1.Follow all directions on screen. We will complete this together step by step. 2.Record all observations in Engineering Notebook. 3.Take turns using the materials. 4.Use academic discourse – be nice, participate, add something to the discussion! 5.NO PLAYING – if you play, your supplies will go away and you will USE the TEXTBOOK. 6.Gather materials, then sit quietly to show you are ready.

Observation 1 1.Break your ½ graham cracker apart (2 pieces). 2.Place each piece on the frosting layer next to each other with the narrow side touching. 1.Push down slightly on both crackers and slowly push them apart. 2.Draw what you see happening and add a brief description.

Observation 2 1.Place graham crackers back on frosting in original position (touching narrow edges). 2.Move graham crackers toward each other, but push down harder on one while gently moving the other. 3.Draw what you see happening and add a brief description.

Observation 3 1.Dip the narrow end of both crackers in the cup of water for a few seconds. 2.Place crackers back on frosting with wet edges facing each other. 3.Slowly push the graham crackers toward each other. 4.Draw what you see happening and add a brief description.

Observation 4 1.Turn crackers so that the wide edges are touching. 1.Move crackers to a clean part of your wax paper. 2.Slowly move one cracker past the other making sure the sides hit. 3.Draw and describe what you see.

Final Steps 1.Under all observations, write a brief reflection of what you saw happening. a. Compare and contrast the observations – what was similar and what was different? Why? b. Which observation caused the most damage? Why? c. What does this have to do with layers of the Earth and tectonic plates? 2.Enjoy the remains of your activity! 3.Complete Exit ticket

Exit Ticket  On a separate sheet of paper answer the following:  Name three types of plate boundaries. Using arrows, show which direction each plate is moving in.