Watersheds - Earth science, science inquiry, observation, properties, variables, & evidence
Key concept of this plan is watersheds and conditions that effect it. Amounts of precipitation and kinds or precipitation, slope, surface area, surface type, amount and kinds of plants, and how of these combine to affect the amount of runoff.
Surface types are a combination of kinds of earth materials (soil, rock, sand, clay), sizes of those materials, kinds of vegetation, amounts of vegetation, human made surfaces, and human made materials.
The activities and discussion focuses on observational evidence from experiences and investigations to reason to create explanations of different watersheds and how different variables can be used to develop descriptions, operational definitions, and models as explanations of watersheds.
Together with the idea of science investigation and the many science processes included can be reviewed or introduced. Examples such as how to use properties, variables, experimental evidence, reasoning, explanations, operational definitions, models, and conclusions to create explanations.
Ranges for these variables can be explored from examples to non examples and amounts in between.
Is it possible that all the rain water might run into a river or no rain water might run into a river?
Draw three kinds of watersheds. One where there would be total run off and likely to be flooding, and one where there would be zero run off and there wouldn't be rivers, and an ideal one in between.
Additional ideas are included in the following curriculum mapping.
Earth Science - Earth's Surface - watershed
What science says - enduring understanding, big ideas, generalizations)
Watersheds are areas of land where water collects and drains into something else (river, lake, stream, etc.) depending on the shape and surface of the land.
Related concepts and facts -
- Soil is composed of (sand, silt, loam, rocks, pebbles, humus) in different amounts. It would be beneficial if students knew this before working with watersheds.
- Different compositions of soil are better at supporting different plant growth in different way.
- Land has different shapes: large slopes, small slopes, steep hills, flat ground.
- Some variables of watersheds that can affect runoff and erosion are different types of land surface (trees, roots, plants, grass, rocky, sandy, concrete...), the different shapes of the land (flat, steep hills, ...), different weather conditions,
- Different substances will erode differently.
- Erosion is the wearing away by wind, water, ice, and chemicals.
- Waves, wind water, and ice shape and reshape the earth’s land surface by eroding rock and soil in some areas and depositing them in other areas, sometimes in seasonal layers.
- Some substances on the land or in the soil (fertilizer, pollution, manure, ...) can erode and and affect the quality of land, water...
Outcome - Watershed
Describe with models, writing, and with pictures watersheds as areas of land where water collects and drains into something else (river, lake, streams, water table, ...
- Describe watershed as ...
- Use observation to communicate watersheds are different depending on the given variables such as: land structure, land surface, and soil characteristics.
- Describe and explain that the flow of water through watersheds is different depending on the surface of the land.
- Describe how watersheds affect our daily lives and relate to the world in which we live.
How science works - science processes
An experiment is when observations are made of objects interacting to collect evidence and reason about them to make explanations and models.
Observation of the properties and how they change are used to predict outcomes and relationships of cause and effect. Those relationships are often explained by describing how the change of one property (variable) affects the change of one or more properties. These are referred to variables.
- Variables are conditions that can be changed and that can affect outcomes.
- Variables relate to observable changes and
- Variables can be changed (manipulated) by experimenting.
Related concepts and facts
- Observations of interactions sometimes show enough variety to see how those changes affect the outcomes.
- We use observational evidence and reasoning to explain interactions in our world.
- We design experiments based on our inferences to better understand our world.
- Variables are observations of a property or characteristic that changes - size, shape, temperature, amount, volume, rate, ... That can have different values.
- A hypothesis describes how variables might change under certain situations. Observed changes can be described as changes of properties (variables).
- When people disagree on an observation, they usually make more and better observations.
- Observation, creativity, and logical argument are used to explain how variable changes effect resulting observations.
- Experiments are often created by changing (manipulating) variables (changing properties).
- The change of one variable (manipulated variable) will interact with another variable (responding variable).
- A science investigation usually involves identifying properties (characteristics) that might interact with others.
- A science investigation usually involves selecting a property that can be changed (changing the property makes it a variable).
- A science investigation usually involves changing the variable (varying a property).
- Changing the variable as part of a science investigation makes that variable the manipulated variable.
- The variable that changes because it interacts with the manipulated variable is the responding variable.
- Sometimes variables can be changed (manipulated) by a person, while not changing others (control), to see how they affect the interactions. This might be done when an interaction is rare or unlikely and a person wants to see what will happen.
Outcome - Variables
Identify variables and describe how they operate to effect other variables. (operational definition).
- Identify variables and suggest how they can be manipulated.
- Identify different variables and describe how they are conditions that can be changed and that can affect outcomes.
- Compare variables. (different types of soil, different types of land, different amounts of water, ...
- Experiment by trying to control all variables, but one, which they will manipulate to determine how that variable operates.
- Describe the relationship between different variables for a watershed.
Outcome - Inquiry experiment
Identify questions that can be answered by creating a model watershed, manipulating variables, and observing the results. (experiment).
- Identify variables that can be used to experiment with and suggest how they can be manipulated.
- Describe how the variables will be represented in the model and how they can be used to simulate different situations to see what change might happen.
- Relate variables in the experiment to the conditions in a watershed they represent. (Slope of the land, different types of soil, different types of vegetation or other surface coverings, different amounts of water, ...
- Experiment by trying to control all variables, but one which they will manipulate to determine how that variable operates.
- Describe the relationship between different variables for as represented by the observations from the experiments.
Activities to provide sufficient opportunities for students to attain the targeted outcomes.
Possible Activity Sequence
- Water drainage
- What is a watershed?
- Crumpled sheet of paper and spray bottle rain
Water drainage activity
Empty half-gallon cardboard milk cartons, gallon plastic milk cartons, samples of soil that are the same size, but have different vegetation (thick, little, no grass), water
Focus question: What effects water drainage?
During this time learners discuss their previous knowledge and understandings and begin to explore water drainage; learners should become disequilibrated.
- Have learners think about what determines how fast and how much water goes into a river after a heavy rainstorm and how this information might help to predict flooding.
- Discuss as a group, write ideas on the board.
- Ask students to think about plants and vegetation covering soil. Can that affect how much water might run off and how fast? Also, have students consider the steepness of a hill and how that might affect water drainage.
- Form groups. Have half of the groups investigate how plants and vegetation affect water drainage; have the other three groups investigate how slope affects water drainage.
- Learners will design their own experiment for their problem and test their experiment.
- Negotiate with students the amount of time they think they need to design their experiment and report back before actually starting. This will allow all students to have input, make suggestions, and do any fine tuning before starting.
- Conduct the experiments, collect observations and organize the results to share with the class.
Focus question: What is a watershed?
Learners will communicate their thoughts and feelings about the experiments they designed; learners should become equilibrated.
- Have the six groups get together and share the information they discovered, the variables they used, and how the activity made them feel.
- Have learners tell what a watershed is and provide vocabulary associated with it ...
- Have them describe what different effects variables have. Such as ....
- Have learners individually draw two watersheds, one where it would be dangerous to build a home and one to show a watershed where someone would rarely have a flooding problem.
- Crumble a sheet of paper, use a mister and mist water on the paper, watch how the water flows, draw some lines with water soluble ink and see how the ink flows. Make comparisons, label the paper model with watershed vocabulary.
Discovery or expanding Watershed Knowledge
- Learners will discover applications for their newly formed knowledge about watersheds.
- Learners consider different variables that could affect watersheds, like fertilizer.
- Have learners come up with a variable on their own that could affect a watershed.
- List variables learners came up with that could affect a watershed.
- Learners draw watersheds, one where it would be dangerous to build a home and one to show a watershed where someone would rarely have a flooding problem.
- Group participation during experiments.
- Overall attitude about nature of science and watersheds