Lesson plan Grade 4 Art & Music
Gosling Falls Dam Cutaway: Drawing How Water Makes Power
A grade 4 art lesson where students draw a labeled cutaway of a dam and show how a river valley changed after the dam was built to make electricity.
Objectives
- Students will draw a labeled cutaway of a dam that shows the reservoir, the falling water, and the turbine.
- Students will explain how a river valley changed over time after a dam was built.
- Students will write labels and a caption explaining how falling water makes electricity.
Vocabulary
- Dam
- A strong wall built across a river to hold back water. Dams store water for people and farms, help prevent floods, and can make electricity.
- Reservoir
- A human-made lake, usually created by a dam, that stores water for later. Reservoirs supply cities and farms and help control floods.
- Turbine
- A machine with blades that spin when water rushes past, like a high-tech waterwheel. Spinning turbines turn generators that make electricity.
- Hydropower
- Electricity made from moving water, usually water falling through a dam. It is a renewable power source that can start up quickly when the electric grid needs it.
Also: cutaway
Teacher overview
Gosling Falls Dam (a fictional dam on the fictional Muddy Boot River near the town of Larkfield) is the setting for a science illustration that visitor centers really use: a cutaway drawing that slices a structure open so viewers can see the parts hidden inside. Students draw a labeled cutaway of the dam, show how the river valley changed after the dam was built, and label how falling water spins a turbine to make electricity. Fourth graders often think a dam only holds water back, so make sure every cutaway also shows the moving water and the turbine, because the movement of water is what actually makes the power.
Procedure
Hook (5 min): Project a photo of a large hydroelectric dam. Ask, "This wall holds back a whole lake, but it also lights up a city. How do you think it does both?" Take a few guesses and list them on the board.
Direct instruction (12 min): Explain the three ideas the drawing must show. First, a dam holds back a river to form a reservoir, a large stored lake. Second, when water is let through, it falls and pushes past a turbine, a wheel that spins. Third, the spinning turbine runs a generator that makes electricity. Explain that the valley changed over time: before the dam it was a river valley, and after the dam much of it filled to become the reservoir. As a real comparison, note that the Hoover Dam was built to make up to about 2,080 megawatts of power. Years of drought have lowered the lake behind it, so today it makes about 30 percent less power than before. Introduce the cutaway idea: an illustrator draws the dam as if sliced open so the turbine inside is visible.
Teacher model (8 min): Draw a simple cutaway on the board: the reservoir on one side, the dam wall, an arrow for water falling through, a circle labeled turbine, and a box labeled generator. Add a small "before" sketch of the open river valley beside an "after" sketch of the filled reservoir. Model one caption: "Falling water spins the turbine, and the turbine runs a generator that makes electricity."
Design work (20 min): Students draw their own labeled cutaway of Gosling Falls Dam. They must label the reservoir, the falling water, and the turbine, add a small before-and-after pair showing the valley change, and write one caption explaining how the water makes power.
Gallery and check (3 min): Students set drawings on their desks. As a formative check, walk the room and confirm each drawing labels the turbine and shows moving water; stop to re-teach any drawing that shows only still water with no turbine.
Closure / exit ticket (2 min): On an index card, each student names two ways the valley changed after the dam was built. Collect and scan the cards.
From Water for Schools (waterforschools.org). This material is in the public domain (CC0) and may be copied, edited, and shared freely.
Answer Key
Exit ticket answer: Accept any two real changes, such as: the open river valley filled with water to make a reservoir lake; the town could now get electricity from the dam; the river below the dam could be controlled to reduce flooding; or people could boat and fish on the new reservoir. A strong answer names changes to both the land and how people use it.
Cutaway check answer: A complete cutaway labels the reservoir (stored water), shows the water falling through the dam, and labels the turbine that the falling water spins. The caption should connect the falling water to the turbine and the turbine to the electricity, in that order.
Differentiation
Support
Provide a lightly printed cutaway outline with the reservoir, dam wall, and turbine circle already placed, so students add the labels, the falling-water arrows, and the caption rather than composing the whole drawing from scratch.
Extension
Ask students to add a second caption explaining one trade-off of the dam, such as how the new reservoir covered land that used to be dry valley, and to show that covered land in their before-and-after sketch.
ELL supports
Pre-teach reservoir, turbine, and cutaway with the teacher's model drawing and a labeled picture card for each word. Allow students to label their drawing with the word cards and arrows and to keep the caption to one clear sentence.
Extensions
Compare the class cutaways with a real cutaway diagram from a dam visitor center or public utility page, and discuss which parts every good cutaway includes. Students can revise their drawings to add any part they missed, such as the generator or the path the electricity takes to town.