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Lesson plan Grade 6 English Language Arts

Explaining Penwick's Water Bill Units: A Grade 6 Writing Lesson

Grade 6 students convert a fictional town's meter units into gallons, then draft an explainer paragraph telling residents what one billing unit really means.

Objectives

  1. Students will convert cubic feet on a water meter into gallons using the factor of 7.48 gallons per cubic foot.
  2. Students will write an explanatory paragraph that defines a billing unit for a reader who has never seen a meter.
  3. Students will revise a vague sentence about water use into a precise one that names the amount and the unit.

Vocabulary

Key words: cubic foot, billing unit, conversion factor, meter reading, explainer

Teacher overview

Many water bills do not report gallons. Many utilities meter in cubic feet, so the figure a household sees is a count of cubic feet rather than a count of gallons, and someone has to do the conversion before the number means anything. This lesson uses the fictional town of Penwick, whose meters count single cubic feet, and asks students to write a short explainer for the utility's newsletter. The misconception this lesson addresses directly is the common assumption that the number printed on a water bill is already gallons, which leads students to conclude that a household used a small fraction of the water it actually used.

Procedure

Hook (5 min): Project the line "Units used on Sunday: 14" and tell students it comes from a Penwick daily meter reading. Ask each student to write on a sticky note how many gallons they think that household used. Collect the notes and post them without commenting on any of them.

Direct instruction (10 min): Explain that Penwick's meter counts cubic feet, and that one cubic foot of water holds 7.48 gallons. Model the conversion once with a number that does not appear on the handout: 6 cubic feet is 6 times 7.48, which is 44.88 gallons. Then model the writing move students will use later, which is defining a unit in terms the reader already knows before giving any figures. Write two sample opening sentences on chart paper and think aloud about which one a reader with no background would follow.

Guided practice (12 min): In pairs, students compare the two sentences on the chart paper and decide which one defines the unit and which one only names it. Ask three pairs to report their reasoning to the class. Then have pairs return to the sticky notes from the hook and revise one guess using the conversion factor, saying aloud how they know.

Independent practice (15 min): Students complete Student Handout items 1 through 7 on their own. Circulate and check that students are writing the unit next to every figure rather than leaving a bare number.

Formative check and closure (8 min): Ask every student to answer one question on the back of the handout: "How many gallons are in one cubic foot, and how do you know?" Read the responses at the door. If more than five students cannot state the factor of 7.48 gallons per cubic foot, reteach the conversion at the start of the next class before collecting the explainer paragraphs.

Explaining Penwick's Water Bill Units: A Grade 6 Writing Lesson — Grade 6 English Language Arts
Name: ____________________________ Date: ______________

Student Handout

Penwick Water Works sends a bill every two months. Residents can also see each day's meter reading online. The meter at each home counts cubic feet of water. One cubic foot of water holds 7.48 gallons. The bill prints the count of cubic feet under the heading "Units used." Many residents call the office because they cannot tell what that number means.

  1. Penwick's meter counts cubic feet, and one cubic foot of water holds 7.48 gallons. In one day the Alvarez family's meter moved 9 cubic feet. How many gallons did the family use that day?
  2. In one or two sentences, explain what "one cubic foot of water" means to a reader who has never seen a water meter.
  3. The Alvarez family's online reading for Sunday says "Units used: 14." Each unit is one cubic foot, and one cubic foot holds 7.48 gallons. How many gallons did the family use that day?
  4. Rewrite this sentence so a reader knows exactly what was measured: "We used a lot of water this month."
  5. The USGS reports that people in the United States commonly use 80 to 100 gallons of water per person each day at home. Four people live in the Alvarez home. Using 80 gallons per person, how many gallons would you expect that home to use in one day?
  6. Which sentence explains the unit better, A or B? Give one reason for your choice. A: "Your bill is measured in units." B: "Your bill counts cubic feet, and one cubic foot is about 7.48 gallons of water."
  7. Write a paragraph of four to six sentences for the Penwick Water Works newsletter. Tell residents what one unit on their bill means, give the conversion to gallons, and end with one example that uses a number from this handout.

From Water for Schools (waterforschools.org). This material is in the public domain (CC0) and may be copied, edited, and shared freely.

Answer Key
  1. Answer: 67.32 gallons.
    Multiply the cubic feet by the gallons in each cubic foot: 9 times 7.48 equals 67.32 gallons.
  2. Answer: Accept any clear definition of a cubic foot as a space one foot long, one foot wide, and one foot deep, holding about 7.48 gallons of water.
  3. Answer: 104.72 gallons.
    Multiply 14 by 7.48. Ten cubic feet is 74.8 gallons and four more is 29.92 gallons, so the total is 104.72 gallons.
  4. Answer: Accept any revision that names both the amount and the unit, such as "We used 14 cubic feet of water on Sunday, which is about 104.72 gallons."
  5. Answer: 320 gallons.
    Four people at 80 gallons per person is 4 times 80, or 320 gallons at home in one day.
  6. Answer: Sentence B.
    Sentence B names the unit and then gives the gallons, so a reader who has never read a meter can picture the amount. Sentence A repeats the word "units" without defining it.
  7. Answer: Accept any paragraph of four to six sentences that defines the unit, states the factor of 7.48 gallons per cubic foot, and closes with an example drawn from item 1, 3, or 5.

Differentiation

Support

Give these students a conversion card that shows the factor and one finished example (5 cubic feet is 37.4 gallons) before they begin item 1. Provide a paragraph frame for item 7 with three sentence starters: "Your bill counts...," "One cubic foot holds...," and "For example, a household that used...."

Extension

Ask students to write a second version of the item 7 paragraph for a different audience, a third grader in a school assembly, and then list the three changes they made and explain why each change suits the younger reader.

ELL supports

Pre-teach "unit," "cubic foot," and "convert" with a labeled drawing of a one-foot box beside a gallon jug. Allow students to answer items 2 and 4 in two short sentences rather than one long one, and provide a word bank containing "cubic foot," "gallons," "meter," and "billing period."

Extensions

Have students draft three questions they would ask a billing clerk about how the meter reading becomes a printed bill, then trade questions with a partner and mark which ones the handout already answers.