Build a Watershed PBS

WGBH Educational Foundation
Type Category
Instructional Materials
Lesson/Lesson Plan , Curriculum
This resource, vetted by NSTA curators, is provided to teachers along with suggested modifications to make it more in line with the vision of the NGSS. While not considered to be “fully aligned,” the resources and expert recommendations provide teachers with concrete examples and expert guidance using the EQuIP rubric to adapted existing resources. Read more here.



This 60 minute activity involves students building a physical model of a watershed and then making observations about how rain water travels over the land, eventually forming rivers and lakes. As an extension, the students take a bucket of water and make observations using actual earth materials.

Intended Audience

Educator and learner
Educational Level
  • Grade 2
Access Restrictions

Free access - The right to view and/or download material without financial, registration, or excessive advertising barriers.

Performance Expectations

2-ESS2-2 Develop a model to represent the shapes and kinds of land and bodies of water in an area.

Clarification Statement: none

Assessment Boundary: Assessment does not include quantitative scaling in models.

This resource is explicitly designed to build towards this performance expectation.

Comments about Including the Performance Expectation
The lesson is aligned with the Performance Expectation. In order to align with the Disciplinary Core Idea, the students would need to make a map of their watershed model, or use a map to build the watershed land features. Students need to extend the lesson to describe water on the planet that is in solid form.

Science and Engineering Practices

This resource is explicitly designed to build towards this science and engineering practice.

Comments about Including the Science and Engineering Practice
Students may make the connection between the model and the natural world more clearly if they are tasked to construct a watershed that is in their own area. They could also first build one creatively and then try to build one that the teacher highlights. The questions (asking how water travels differently across different landforms) are very relevant to the practice of modeling with affordances and limits inherent in the practice (e.g., plastic doesn’t work like soil, but water still slides over land in a similar way).

Disciplinary Core Ideas

This resource is explicitly designed to build towards this disciplinary core idea.

Comments about Including the Disciplinary Core Idea
The lesson addresses the Core Idea with modeling instead of mapping, but doesn’t actually get to mapping or using maps to understand their purpose. With support from the teacher, the students might try to observe and analyze a map of a familiar (local) watershed, and find similar features in the model. Next they could make a map of their own watershed.

Crosscutting Concepts

This resource is explicitly designed to build towards this crosscutting concept.

Comments about Including the Crosscutting Concept
The teacher could be explicit about the Crosscutting Concept by prompting for the use “patterns” as a lens. She/he could ask questions like, “What is a pattern?” What is a pattern that we see in the model?” “Do others agree the idea is indeed about a pattern, why?” As a class, it might be fruitful to work on a class-made definition of a pattern which can be routinely inspected and revised.

Resource Quality

  • Alignment to the Dimensions of the NGSS: The lesson provides students with a relevant phenomenon and helps students make connections between the world outside the school and the watershed model in the classroom, building on prior knowledge with an initial experience. The lesson uses scientifically accurate scientific information to support students’ three‐dimensional learning. The lesson would benefit from enhanced application to the local neighborhood near the school. For instance, students could go for a walk and analyze and discuss parts of the watershed that the neighborhood is situated in. Or, students could investigate local events that are related to water health or water flow in the local area.

  • Instructional Supports: There are embedded questions that will press students to be productive and engage with all three dimensions of the NGSS. The multiple avenues to access the ideas in the lesson will support students who have less correct science knowledge.

  • Monitoring Student Progress: The lesson includes questions to ask the whole group, and small group activities as well. The responses to the questions in discussion would form an informal assessment, but a written artifact would need to be created. If the teacher needed to assess an individual student, she might use a question as an exit slip instead of as a discussion prompt. For example, ““Which one is better for showing patterns in water flow, a model or a map, and why?

  • Quality of Technological Interactivity: There is little use of interactive technology involved except for downloadable materials.