4. The Physical Setting
C. Processes That Shape the Earth: (Geology-Related Benchmarks)
Grades K - 2: By the end of the 2nd grade, students should know that:
- Chunks of rocks come in many sizes and shapes, from boulders to grains of sand and even smaller.
- Change is something that happens to many things.
Grades 3 - 5: By the end of the 5th grade, students should know that:
- Rock is composed of different combinations of minerals. Smaller rocks come from the breakage and weathering of bedrock and larger rocks. Soil is made partly from weathered rock, partly from plant remains--and also contains many living organisms.
Grades 6 - 8: By the end of the 8th grade, students should know that:
- Sediments of sand and smaller particles (sometimes containing the remains of organisms) are gradually buried and are cemented together by dissolved minerals to form solid rock again.
- Sedimentary rock buried deep enough may be reformed by pressure and heat, perhaps melting and recrystallizing into different kinds of rock. These re-formed rock layers may be forced up again to become land surface and even mountains. Subsequently, this new rock too will erode. Rock bears evidence of the minerals, temperatures, and forces that created it.
- Thousands of layers of sedimentary rock confirm the long history of the changing surface of the Earth and the changing life forms whose remains are found in successive layers. The youngest layers are not always found on top, because of folding, breaking, and uplift of layers.
Grades 9 - 12: By the end of the 12th grade, students should know that:
- The formation, weathering, sedimentation, and reformation of rock constitute a continuing "rock cycle" in which the total amount of material stays the same as its forms change.
- The slow movement of material within the Earth results from heat flowing out from the deep interior and the action of gravitational forces on regions of different density.
|
From Benchmarks for Science Literacy