MI BIG
Geosphere V.1
Map (html) | Map
(Inspiration)
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All students will describe the earth's surface.
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All students will describe and explain how the
earth's features change over time.
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All students will analyze effects of technology on
the earth's surface and resources.
Overview
As humans we are the keepers of the earth. We notice that
our planet, the earth, looks different all over its surface. These
features, lakes, rivers, mountains, and sand dunes, change with time. Some
of these changes happen rapidly, through earthquakes or volcanism. Other
changes happen over such long periods of time that we find it hard to
comprehend. These slow changes can create huge Earth features like the
Grand Canyon and the Great Lakes.
People also change the earth. Both quickly and slowly, our
existence on this planet changes how the planet looks, how it functions,
and how it sustains us. We draw from the Earth resources for our way of
life. We are constantly searching for ways to continue our resource use
while minimizing the impact of our existence on our planet.
Essential Background Narratives
Describe the
earth's surface.
Describe
and explain how the earth's features change over time.
Analyze
effects of technology on the earth's surface and resources
Elementary students are likely unaware of the size, shape
and variety of surfaces of the earth beyond their neighborhoods, but soon
learn that all the geosphere is made of similar material. They learn that
under the pavement and the ground floors are soil, rock, and water. The
students begin to realize that the surface of the earth is extremely
uneven, but the difference between mountains, hills, rocks, pebbles, and
soil is only size not composition. They learn that mountains are formed
and worn down into the other features. Through various media and field
trips, students observe that beyond their sidewalks, fields and
neighborhood buildings, there are mountains and valleys, hills and plains,
lakes and ponds, rivers and creeks, deserts and rainforests. Through the
study of maps, an understanding develops that the earth is round and that
the features of the earth are diverse.
As students gain understanding, they start to explore the
dynamics of the geosphere. They come to realize that the earth's features
are constantly changing, some of these changes are immediate and some take
eons. Wind and water erode away mountains and hills. Ice and heat break
apart rocks. Rivers cut new valleys and dams form new lakes. Volcanoes and
earthquakes form new mountains and hills. Wind and water combine to build
sand dunes and then turn around and erode them away. The forces that work
to change the surface of the earth in this continuing dynamic are
tremendous and sometime even catastrophic. A volcano can explosively form
a mountain or island in a matter of hours, while rivers can take decades
to carve out valleys.
The evidence for these changes is abundant. By studying
rock layers, and fossils, (i.e., mineralized replacements or casts of
ancient life forms), students learn the history of the geosphere. They
discover that these fossils are found in many places, and that rock layers
can become inverted. Marine plants and animals are found on mountaintops
and in limestone deposits in the Great Lakes area. Creatures from rain
forests have left fossilized remains in current deserts, and plains
animals are found in frozen in artic ice. From road cuts they will see how
the earth is folded to a point where layers of rock are reversed. In the
Great Lakes Basin they observe a history that goes from salt-water seas,
to inland swamps, to high plateaus, to the largest collection of fresh
water on the planet.
Students will continue to gain understanding of the
geosphere as they discover that similar processes form rocks and minerals.
They will learn of the tremendous amount of heat and pressure involved in
their formation. They will also observe how changes in temperature from
melting to freezing and vise versa changes big features into little ones.
Rocks are fractured through this process. Water in small cracks and
crevices of rocks can freeze, expanding as it freezes and breaking the
rock into small pieces. Students will notice how microorganisms help turn
rocks into soil, and how they turn organic materials back into minerals,
thus returning needed materials to the earth.
With the help of media presentations about volcanoes and
earthquakes, students will observe the movement of the Earth's crust. This
will lead to an understanding of the dynamics of the earth's interior- its
core, a dynamic that can build mountains. From this knowledge of the
fluidity, tremendous heat and pressure that are involved in the dynamics
of the earth's core, comes an understanding of what leads scientists to
theorize the movement of plates in the earth, the study of plate
tectonics.
Entwined with this natural change is the effect of humans
on the geosphere.
Human activities have caused overuse and pollution of the features of the
earth's surface. Earth's resources are either renewable or nonrenewable.
People get their transportation, building materials, energy, and water
directly from the geosphere. The geosphere provides all life with their
habitats. People must continually seek to reduce the adverse effects of
our activities on the geosphere. This may be done through the practice of
reduction of material use, the reuse of materials, the recycling of
manufactured materials and the further development of new technologies.
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