Contributed by: Oregon State Department of Education

Description:

Students will design and conduct an open-ended investigation using a variety of earth materials to answer a question posed by the teacher: How does the erosion of sand compare with the erosion of gravel? After producing evidence that addresses this question, they will generate their own question that could be answered with further scientific inquiry.

The task assesses students' understanding of scientific inquiry including the following skills: observation, data collection, measurement, graphing, scientific questions.

This task is designed to take students approximately 4 hours.

Overall Task Content Area:

Earth Science

Specific Knowledge Areas:

Identify causes of Earth surface changes

Performance Expectations:

• conducting investigations
• using equipment
• gathering, organizing, and representing data
• formulating conclusions from investigational data

National Science Education Standards:

8 A SI 1: Abilities necessary to do scientific inquiry: Grades 5-8

1.1 Identify questions that can be answered through scientific investigations. Students should develop the ability to refine and refocus broad and ill-defined questions. An important aspect of this ability consists of students' ability to clarify questions and inquiries and direct them toward objects and phenomena that can be described, explained, or predicted by scientific investigations. Students should develop the ability to identify their questions with scientific ideas, concepts, and quantitative relationships that guide investigation.

1.2 Design and conduct a scientific investigation. Students should develop general abilities, such as systematic observation, making accurate measurements, and identifying and controlling variables. They should also develop the ability to clarify their ideas that are influencing and guiding the inquiry, and to understand how those ideas compare with current scientific knowledge. Students can learn to formulate questions, design investigations, execute investigations, interpret data, use evidence to generate explanations, propose alternative explanations, and critique explanations and procedures.

1.3 Use appropriate tools and techniques to gather, analyze, and interpret data. The use of tools and techniques, including mathematics, will be guided by the question asked and the investigations students design. The use of computers for the collection, summary, and display of evidence is part of this standard. Students should be able to access, gather, store, retrieve, and organize data, using hardware and software designed for these purposes.

1.7 Communicate scientific procedures and explanations. With practice, students should become competent at communicating experimental methods, following instructions, describing observations, summarizing the results of other groups, and telling other students about investigations and explanations.

1.8 Use mathematics in all aspects of scientific inquiry. Mathematics is essential to asking and answering questions about the natural world. Mathematics can be used to ask questions; to gather, organize, and present data; and to structure convincing explanations.

8 D ESS 1: Structure of the earth system: Grades 5-8

1.3 Land forms are the result of a combination of constructive and destructive forces. Constructive forces include crustal deformation, volcanic eruption, and deposition of sediment, while destructive forces include weathering and erosion.

4 D ESS 3: Changes in the earth and sky: Grades K-4

3.1 The surface of the earth changes. Some changes are due to slow processes, such as erosion and weathering, and some changes are due to rapid processes, such as landslides, volcanic eruptions, and earthquakes.

(Use the "hot" link on the PALS home page to check the full text of related National Science Education Standards, if desired.)

National Council of Teachers of Mathematics:

AL1: Understand patterns, relations and functions:
Grades 6-8 f. represent, analyze, and generalize a variety of patterns with tables, graphs, words, and, when possible, symbolic rules

DAP3: Develop and evaluate inferences and predictions that are based on data:
Grades 6-8 e. use conjectures to formulate new questions and plan new studies to answer them

PS2: Solve problems that arise in mathematics and in other contexts:
Grades 6-8

REP1: Create and use representations to organize, record, and communicate mathematical ideas:
Grades 6-8

General Instructions to the Teacher:

This task is designed to take students approximately 4 hours to complete.

Students should be ready to work as soon as periods begin. A central supply area, if needed, should be easily accessible. All supplies should be clearly labeled.

Materials for "Erosion":

The teacher will need:

• steam table (shallow pan-type containers can be used instead of stream tables)
• earth materials (for example, loam, silt or clay), and gravel (e.g., aquarium gravel, pea gravel, 3/4 minus).
• water
• paper towels
• watering bottle
• obstructions such as stones, sticks
• plant materials (e.g. grass)

Advance Preparation:

• Introduce your students to stream tables.
• Students must understand that they need a container to collect runoff water and paper towels to absorb spills. They must understand how to prepare the various Earth materials and how to position the water source.
• With the students, spend some time running water through sand, soil, and gravel. Have them observe what happens and record their findings using words and pictures. Have the students discuss and compare their results in small groups and then as a whole class.
• After familiarizing your students with stream tables, a variety of earth materials, the process of erosion, you will ask your students to develop a procedure to answer a question using the scientific inquiry process and skills. Sample questions for investigation might include: Does sand erode as easily as gravel? How does the rate of water flow affect erosion? Will slope of the table affect erosion? How will obstructions or plants affect erosion?
• Include background information about set-up and use of stream tables. Include diagram of set-up.

Safety:

• Be careful.
• Teachers and students should always exercise appropriate safety precautions and utilize appropriate laboratory safety procedures and equipment when working on science performance tasks.

Extensions/modifications:

• To target the specific NCTM standard(s) to be measured, ask students to construct a graph to represent data