San Francisco Geology: Evidence of Change Over Time
© Kwong Yee Cheng
We have Bilingual Educators! Let us know if any students or chaperones in your class might benefit from activities taught in Cantonese, Mandarin, or Spanish.
- use a variety of scientific tools to identify evidence of erosion, and stability in diverse geological sites
- develop arguments from evidence to compare and contrast benefits and risks of certain locations
How do geologists know that a building will be in a stable location over time? In this program, students take on the role of working as geologists for the city of San Francisco. The students’ mission is to explore the properties of rocks at specified locations in order to determine if evidence shows one site is more geologically stable than others. Students rotate through investigation stations to collect evidence by using iPad microscopes, stereoscopes, hardness tests, and time lapse pictures. The class then uses the evidence from the investigations to engage in scientific arguments that help them make recommendations for the future site of a water-recycling factory.
This field trip program compliments the FOSS Curriculum: Soils, Rocks and Landforms. We recommend the field trip take place in the middle or at the end of your unit.
Another option to prepare your students is to teach the Rock Cycle Roundabout Game to help your students understand geologic processes over time. Use the link below to download the lesson.
Science and Engineering Practices
- Planning and Carrying Out Investigations: Make observations and/or measurements to produce data to serve as the basis for evidence for explanation of a phenomenon or test a design solution.
- Constructing Explanations and Designing Solutions: Use evidence (e.g., measurements, observations, patterns) to construct or support an explanation of design a solution to a problem
- Engaging in Argument from Evidence: Construct and/or support an argument with evidence, data and/or a model.
Disciplinary Core Idea
- 4-ESS2.A: Earth Materials and Systems: Water, ice, wind, living organisms, and gravity break rocks, soils, and sediments into smaller particles and move them around.
- Stability and Change: Change is measured in terms of differences over time and may occur at different rates
- Structure and Function: Different materials have different substructures, which can sometimes be observed.
Related Performance Expectations
Remember, performance expectations are not a set of instructional or assessment tasks. This field trip activity is just one of many that could help prepare your students to perform the following hypothetical tasks that demonstrate their understanding:
4-ESS2-1. Make observations and/or measurements to provide evidence of the effects of weathering or the rate of erosion by water, ice, wind, or vegetation. [Clarification Statement: Examples of variables to test could include angle of slope in the downhill movement of water, amount of vegetation, speed of wind, relative rate of deposition, cycles of freezing and thawing of water, cycles of heating and cooling, and volume of water flow.]
- Earth Sciences
- 5a. Students know some changes in the earth are due to slow processes, such as erosion, and some changes are due to rapid processes, such as landslides, volcanic eruptions, and earthquakes.
- 5c. Students know moving water erodes landforms, reshaping the land by taking it away from some places and depositing it as pebbles, sand, silt, and mud in other places (weathering, transport, and deposition).
- Investigation and Experimentation 6a. Differentiate observation from inference (interpretation) and know scientists’ explanations come partly from what they observe and partly from how they interpret their observations.
- Investigation and Experimentation 6h. Draw conclusions from scientific evidence and indicate whether further information is needed to support a specific conclusion.