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Earth History Unit Overview

Unit Summary  


We start our unit with an exploration of deep geologic time, then use that concept to explore the structure of the Earth and how those structures change over time. Plate tectonics, the underlying explanatory theory of geology is then explored through maps, earthquakes and volcanoes. Minerals and rocks are identified for the stories they can tell us about the cycles of Earth through time and how landforms develop.  That information is then used for an exploration of local geology. The final portion of the unit combines both the Life on Earth unit and the Earth’s History unit with an exploration of evolution through time.        

Big Ideas

Earth’s Geosphere

  • 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. 4C/M3
  • Sedimentary rock buried deep enough may be re-formed 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. 4C/M4
  • 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. 4C/M5
  • The earth first formed in a molten state and then the surface cooled into solid rock. 4C/M10** (ASL)
  • The earth is structured into several different layers, each with different properties.
  • The outer layer of the earth—including both the continents and the ocean basins—consists of separate plates. 4C/M11** (BSL)
  • The earth's plates sit on a dense, hot, somewhat melted layer of the earth. The plates move very slowly, pressing against one another in some places and pulling apart in other places, sometimes scraping alongside each other as they do. Mountains form as two continental plates, or an ocean plate and a continental plate, press together. 4C/M12** (BSL)
  • There are worldwide patterns to major geological events (such as earthquakes, volcanic eruptions, and mountain building) that coincide with plate boundaries. 4C/M13** (BSL)
  • Vibrations in materials set up wavelike disturbances that spread away from the source. Sound and earthquake waves are examples. These and other waves move at different speeds in different materials. 4F/M4
  • Geological time and Earth’s history big idea needed-connection to evolution
  • Many variables (materials, forces, earth composition, structural design) determine the stability of a structure.
  • The engineering design process is a useful tool for solving a variety of engineering problems.


  • Matter is cycled through nature (carbon, nitrogen, water).
  • All matter is made up of atoms, which are far too small to see directly through a microscope. 4D/M1a
  • The atoms of any element are like other atoms of the same element, but are different from the atoms of other elements. 4D/M1b*
  • Atoms may link together in well-defined molecules, or may be packed together in crystal patterns.
  • Different arrangements of atoms into groups compose all substances and determine thecharacteristic properties of substances. 4D/M1cd*
  • There are only about 100 different elements and all matter is made of some combination ofthem (compounds)
  • No matter how substances within a closed system interact with one another, or how theycombine or break apart, the total mass of the system remains the same. 4D/M7a*
  • The idea of atoms explains the conservation of matter: If the number of atoms stays the same no matter how the same atoms are rearranged, then their total mass stays the same. 4D/M7b
  • A substance has characteristic properties such as density, melting point, freezing point and solubility, all of which are independent of the amount of the substance and can be used to dentify it. 4D/M10** (NSES)

         •  Energy is stored in many different forms.
         •  Energy is neither created nor destroyed, it is transformed from one form to another.
         •  Most of the energy on Earth can be traced back to nuclear fusion in the sun’s core.
         •  Energy flows through all dynamic systems on Earth.


  • The Engineering Design Process is an effective tool for solving a variety of engineering problems
  • A system is a group of interacting, interrelated, or interdependent elements forming a complex whole
  • The form of a structure (or its parts) is determined by its function and may be affected by the environment. (For example, the design and materials used in houses throughout the world differs based on the climate & environment.)
  • Materials have different characteristics or properties (e.g., shape, flexibility, texture, color, texture, hardness, color)
  • Objects may be made of different materials depending on the object’s use and the properties required (e.g., strength, hardness, flexibility, etc.)
  • Strength and stability can be enhanced depending on the way a material is used (e.g., the use of triangles in bridges and skyscrapers)
  • Many variables (materials, forces, earth composition, structural design) determine the stability of a structure.



Content Learning Expectations


Earth’s Geosphere

  • Explain the formation of different types of rocks and their characteristics (composition, conditions under which they form, time to form).
  • Given a rock sample, students will provide evidence of the conditions under which it formed, what it is comprised of, and how it may have changed over time.
  • Describe the structure of the earth
  • Create a model to show the stages of the Rock Cycle
  • Compare and contrast the different forces that create and destroy rocks.
  • Identify the relative age of rock layers in relation to their position in a cross-section.
  • Give evidence that supports the theory of plate tectonics
  • Explain the role of plate tectonics in shaping the Earth
  • Interpret topographic maps, remote sensing data to identify surface features and explain how they formed
  • Visually represent how Earth has changed throughout its history


  • Describe how atoms and molecules are the building blocks of matter (e.g., cell parts, nutrients, minerals)
  • Categorize or classify a set of minerals according to characteristic properties
  • Identify and/or describe the elements that are most common in both living and nonliving things on Earth
  • Classify rocks according to physical and chemical properties
  • Demonstrate the use of saturated solutions in crystal formation [crystal lab)


  • Describe how matter and energy change from one form to another in living things and in the physical environment
  • Give evidence to show that the total amount of matter in the environment stays the same even as its form and location change
  • Describe the measureable properties of waves (velocity, frequency, wavelength, amplitude and period) (MA)
  • Recognize that waves generally move faster through a solid than through a liquid and faster through a liquid than through a gas (MA)
  • Collect and analyze data to describe how physical characteristics of a vibrating object effect frequency and amplitude of a wave (MA) 

Engineering (Earthquake Resistant Structures)

  • Describe the forces that act on a structure during an earthquake.
  • Complete the engineering design cycle to build a model structure when given limited materials and set criteria.
  • Use the design process to evaluate the stability of their structure.
  • Identify evidence of forces (tension, compression, shear, torsion, gravity, normal force, bending, etc) interacting in the system
  • Evaluate properties and suitability of materials used to build structures.