Lesson OverviewIn this 50-minute lesson, students will learn about how water flows naturally. They will also learn about how man-made or animal-made structures can redirect the flow of water. Standards & ObjectivesK-ESS2-2 Construct an argument supported by evidence for how plants and animals (including humans) can change the environment to meet their needs..K-ETS1-1 Ask questions, make observations, and gather information about a situation people want to change to define a simple problem that can be solved through the development of a new or improved object or toolK-ETS1-3 Analyze data from tests of two objects designed to solve the same problem to compare the strengths and weaknesses of how each performs.CCSS.MATH.CONTENT.2.MD.A.3 Estimate lengths using units of inches, feet, centimeters, and metersResources & MaterialsVideo on Beaver Dams https://www.youtube.com/watch?v=yJjaQExOPPYVideo on Building the Hoover Dam https://www.youtube.com/watch?v=n9Gy_1Ppw5UVideo on How Water Flows https://www.youtube.com/watch?v=RqZbsr32n0cMaterials: bottled water, construction paper, blocks, wire, string, Playdoh, tape, scissors, pipe cleaners, popsicle sticks (a variety of scraps and building supplies)LessonStage 1: Observations & Comparisons (10 min)Watch videos and look at pictures of dams, both man made and those occurring naturally. Compare the sizes, shapes, and materials used. Discuss why humans might build a dam. Discuss what happens to the water flow when a dam is put in place. Question how adjusting the size, shape, or position of the dam could change the flow.Stage 2:  Designing & Building (30 min)Imagine city workers need to adjust the flow of a river to put in new electrical poles. You will need to design a dam that will redirect the river to another location.  Consider what materials you can use that will withstand water flow for this project. Sketch and design a city dam structure. List materials, and design the model.Stage 3 Testing & Reflection (10)Test each design by creating a "river" with water flowing into the structure. Discuss height and direction of water flow. What adjustments need to be made? Which materials worked well for this project. Compare to real-world scenarios: What materials would be needed for a real river?