7th Grade Earth Science

There are many cycles throughout the universe.

1. The earth turns daily on its axis. (AKSci - A.4)

2. The earth's axis is tilted relative to the plane of the orbit around the sun, causing the seasons. (AKSci - A.4)

o Create a model that illustrates the motions and positions of the earth relative to the sun and describe the correlation between these motions and the day/night cycle, time zones, and seasons. (for #1 and #2)

3. The cycling of water plays an important role in determining climatic patterns. Water evaporates from the surface of the earth, rises and cools, and then condenses into rain or snow. The water falling on land collects in rivers and lakes, soil, and porous layers of rock, and much of it flows back into the ocean. (AKSci - A.5, A.9)

o Create a model illustrating the water cycle.

4. 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. (AKSci - A.7)

o Investigate through experimentation, the properties of materials making up earth's crust (e.g., rocks and minerals).

o Relate the structure of rocks and minerals to their formation.

There is order in the universe.

1. 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. (AKSci - A.7)

o Explain the order of events involved in the formation of a given geologic profile.

2. The earth is mostly rock. Three-fourths of its surface is covered by a relatively thin layer of water (some of it frozen), and the entire planet is surrounded by a relatively thin blanket of air. The other planets have compositions and conditions very different from the earth's. (AKSci - A.4)

o Debate whether the ocean is amazingly deep or amazingly shallow.

o Make a cross-section scale model of the earth.

Many of the earth's features are the result of processes which occur over long periods of time.

1. Although weathered rock is the basic component of soil, the composition and texture of soil and its fertility and resistance to erosion are greatly influenced by plant roots and debris, bacteria, fungi, worms, rodents, and other organisms. (AKSci - A.7)

o Compare soil makeup for a variety of soil types.

2. 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. (AKSci - A.7)

o Using different percentages of clay, sand, cement, and water, simulate the formation of sedimentary rock.