Worksheet Grade 5 English Language Arts
Reading Hoover Dam's Numbers: A Grade 5 Nonfiction Worksheet
A grade 5 worksheet on how Hoover Dam makes electricity from flowing water, pairing vocabulary and sequencing questions with the dam's real power-plant capacity.
Objectives
- Students will explain how Hoover Dam's power plant generates electricity from flowing water.
- Students will define vocabulary such as turbine and generator using context from the passage.
- Students will use the passage's stated power-plant capacity to answer a comparison question.
Vocabulary
- Turbine
- A machine with blades that spin when water rushes past, like a high-tech waterwheel. Spinning turbines turn generators that 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.
Also: generator, capacity
Teacher overview
Hoover Dam stands on the Colorado River, holding back a large reservoir and using the force of moving water to generate electricity for millions of people across the Southwest. This worksheet gives students a short factual description of how the dam makes electricity, then asks them to define vocabulary, reason about cause and effect, and apply the passage's main verified number, the dam's power-plant capacity of 2,080 megawatts, to a comparison question. The passage also notes that drought has cut how much power the plant actually makes today. A common misconception worth addressing directly: students often assume a dam "makes" water, when its power plant instead uses water that is already flowing to spin turbines that generate electricity.
Student Worksheet
Read the description of Hoover Dam, then answer the questions.
Hoover Dam sits on the Colorado River. It holds back a large reservoir behind a wall of concrete. Water from the reservoir is released through openings near the bottom of the dam. As the water rushes through, it spins the blades of machines called turbines. Each spinning turbine turns a generator. A generator is a machine that turns motion into electricity. Hoover Dam's power plant can produce about 2,080 megawatts. That is the most electricity the plant can make when its turbines run at full power. Years of dry weather have lowered the water in Lake Mead, the reservoir behind the dam. Because of this, the plant now makes about 30 percent less power than it used to. The electricity travels through power lines. It reaches homes, schools, and businesses far from the dam. Hoover Dam's power plant does not burn fuel the way a coal or gas plant does. It only needs flowing water to keep its turbines spinning.
- What river does Hoover Dam sit on?
- Define "turbine" using the description's explanation.
- Put these events in order. Water spins turbines. Water is released from the reservoir. A generator makes electricity. The reservoir holds back water.
- What is Hoover Dam's power-plant capacity? What does that number mean in the passage?
- Why does Hoover Dam's power plant not need to burn fuel? Use details from the passage.
- Find the sentence that explains what a generator does. Write the sentence.
- A student says Hoover Dam "creates" the water for its electricity. Explain why this is incorrect. Use details from the passage.
- Suppose a smaller dam's power plant makes 500 megawatts at full power. Hoover Dam's plant can make about 2,080 megawatts at full power. Which dam's plant could make more electricity? About how much more?
- Why might it matter that Hoover Dam's electricity travels far from the dam? Use reasoning from the passage.
From Water for Schools (waterforschools.org). This material is in the public domain (CC0) and may be copied, edited, and shared freely.
Answer Key
- Answer: the Colorado River. The passage states Hoover Dam sits on the Colorado River.
- Answer: a machine with blades that spin when water rushes through. The passage describes turbines as spinning when released water rushes through the dam's openings.
- Answer: the reservoir holds back water, water is released from the reservoir, water spins turbines, a generator makes electricity. This is the order the passage describes the process happening in.
- Answer: about 2,080 megawatts. The passage states this is the most electricity the plant can produce when its turbines run at full power.
- Answer: because the plant only needs flowing water, not burned fuel, to keep its turbines spinning and generate electricity, unlike a coal or gas power plant.
- Answer: "A generator is a machine that turns motion into electricity." This is the sentence that explains what a generator does.
- Answer: The passage explains that Hoover Dam holds back water that already exists in the Colorado River; it does not create new water; it only releases the water already stored behind it.
- Answer: 1,580 megawatts. Hoover Dam's power plant could produce more electricity at full power. 2,080 minus 500 equals 1,580, so Hoover Dam's plant could produce that much more electricity.
- Answer: Answers will vary but should reason that electricity generated at the dam has to reach people who live far away, which is why the passage specifically mentions power lines carrying it to homes, schools, and businesses elsewhere.
Differentiation
Support
Provide a simple four-step picture sequence (reservoir, release, turbine, generator) with the passage's key sentence printed under each picture, so students can match rather than write from memory for item 3.
Extension
Ask students to reason, using only the passage, what would likely happen to the amount of electricity Hoover Dam's power plant could produce if less water were released through its turbines, and write two sentences explaining their reasoning.
ELL supports
Preteach "turbine," "generator," and "reservoir" with a simple diagram showing water flowing from a lake, through a spinning wheel, to a light bulb. Allow item 9 to be answered orally with teacher prompting.