Science Assessment ~ Ideas ~ The outer layer of the earth – including the continents and the ocean basins

Key Idea: When continental plate material from one plate presses against another plate, the continental plate material is forced upward, forming mountains.
-and-
When oceanic plate material from one plate presses against another plate, it can slide under the other plate, sinking deep into the earth.

Sub-Ideas
Items & Student Performance
Misconceptions
NGSS

These items have been aligned to more than one key idea. To view the sub-ideas click on a key idea below.

When continental plate material from one plate presses against another plate, the continental plate material is forced upward, forming mountains.
Students are expected to know that:
1. Continental plate material makes up continents, oceanic plate material makes up ocean basins, and the top part of any plate can be made of either oceanic or continental plate material or continental plate material in some places and oceanic plate material in other places.
2. Continental plate material is made of rock that is less dense and much thicker than oceanic plate material.
3. When two plates press together, if one plate has plate material at its edge that is less dense than the edge of the other plate, the less dense plate material will crumple upward, creating a bend or fold in the plate material but not causing the plate to break into smaller pieces of rock. If the plate material is approximately the same density on both edges, the edges of both will crumple upward.
4. When continental plate material from one plate presses against oceanic plate material from another plate, the continental plate material crumples up over the oceanic plate material.
5. As continental plate material from one plate presses against continental plate material from another plate, the edges of both plates crumple up, creating a bend or fold in the plate material but not causing the plate to break into smaller pieces of rock.
6. The result of a plate crumpling up is mountains, which are composed of the continental plate material that has been folded upward.
7. The crumpling up of plate material reduces the area of the earth’s surface covered by a plate.
8. New mountains have formed throughout earth’s history, and mountains continue to develop as plates move and press together.
Boundaries:
1. Students are not expected to know that continental plate material from one plate can sink under other continental plate material from another plate.
2. Students are not expected to know that when two plates press together, plate material breaks (e.g., faults occur) as well as bends.
When oceanic plate material from one plate presses against another plate, it can slide under the other plate, sinking deep into the earth.
Students are expected to know that:
1. Some oceanic plate material is denser than other oceanic plate material.
2. When oceanic plate material from one plate presses against another plate that is less dense than it (made of continental or oceanic plate material), it will slide beneath the other plate toward the interior of the earth.
3. The edge of the denser plate will continue to fall toward the interior of the earth as long as the two plates move toward each other.
Boundaries:
1. Students are not expected to know the term “subduction.”
2. Students are not expected to know what makes some plate material denser than other plate material.
3. Students are not expected to know that continental plate material sometimes can slide under continental plate material.

Percent of students answering correctly (click on the item ID number to view the item and additional data)
Item ID Number	Knowledge Being Assessed	Grades 6–8	Grades 9–12	Select This Item for My Item Bank
PT027003	Oceanic plate material is pushed downward when it presses against continental plate material.	39%	46%

Frequency of selecting a misconception
Misconception ID Number	Student Misconception	Grades 6–8	Grades 9–12
PTM129	Continental plate material is pushed beneath oceanic plate material when two plates push together (AAAS Project 2061, n.d.).	25%	22%
PTM130	When two plates push into each other, both plates will stop moving (AAAS Project 2061, n.d.).	20%	17%
PTM131	When two plates push together, the edges of the plates break into small pieces (AAAS Project 2061, n.d.).	16%	15%

Frequency of selecting a misconception was calculated by dividing the total number of times a misconception was chosen by the number of times it could have been chosen, averaged over the number of students answering the questions within this particular idea.

No NGSS statements are associated with this idea in the selected project.

Science Assessment

Key Idea: When continental plate material from one plate presses against another plate, the continental plate material is forced upward, forming mountains. -and-When oceanic plate material from one plate presses against another plate, it can slide under the other plate, sinking deep into the earth.