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SWBAT create a model of tributaries and identify erosion and deposition in a stream model.

Big Idea

Tributaries can branch off of a stream and can join together to form a larger stream.

Warm Up

10 minutes

I begin this lesson by sharing with students the definition of a tributary. We discuss the local stream that we visit and follow its path until it reaches a major river and eventually the ocean. We discuss that the local stream is a tributary of the larger river and that our stream has its own system of tributaries. Making this link to our shared experience of visiting the stream helps students to better understand the new vocabulary and to develop a personal connection to their learning.

Student-Conducted Lab

40 minutes

In this lab, I focus on creating evidence based conclusions. As a result of this focus, I begin the lab portion of the lesson by reviewing the importance of recording accurate results and sharing conclusions. I discuss with students how, in order to make progress and learn, scientists record data and share their results with other scientists so that the knowledge gained by one person can be built upon by others.

I review the purpose of the lab and procedures for student work by displaying the tributaries lab worksheet on the document camera and reading the relevant sections aloud. In this lab, the students pour water through a cup with three holes. The cup creates three distinct streams in the stream table. After students have completed their lab work, I ask them to create a bird's eye view drawing of their stream table and to cite observational evidence as they draw conclusions about their stream table. The lab worksheet asks students to consider how the stream created in this lab differs from streams created in previous labs, to , and to describe the soil deposit created in this lab compared to other labs.

A video of students completing this lab can be found here. A sample of one student's completed lab worksheet can be found here.


10 minutes

To close the lesson, I ask students to view a new set of photo cards which show streams of water interacting with the land. I ask students to use their observational skills to record what they notice about the land and water in each photo card. I ask the students to record their thinking on the photo card worksheet. I provide time for students to share their work with their science partners at the end of the lesson. This strategy serves as a formative assessment. Students must utilize the knowledge and vocabulary that they have gained to compose compelling explanations of the interactions of land and water depicted in the photo cards. I review important content and vocabulary as needed in response to the students' work.

If the lesson is running long, this portion can be completed on a subsequent day.