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Worksheet Grade 10 English Language Arts

Does the Rowanfield Filter Letter Prove Its Claims?

A grade 10 ELA worksheet in which students test a fictional home-filter sales letter against the town's own water data and write a short evidence-based evaluation.

Objectives

  1. Students will separate the claims in a persuasive letter from the evidence offered for them.
  2. Students will identify hedged, unsupported, and irrelevant evidence in a sales appeal.
  3. Students will write a short argument evaluating whether the letter's evidence supports its recommendation.

Vocabulary

Turbidity
Turbidity is a measure of how cloudy or murky water looks because of tiny particles floating in it. Clear water has low turbidity, and muddy water has high turbidity.
Contaminant
A contaminant is anything in water that should not be there, whether it is a germ, a chemical, or too much of a natural mineral, that could make the water unsafe or unpleasant to use. Treatment plants are built specifically to find and remove contaminants before water reaches the tap.

Also: claim, hedge, sales appeal

Teacher overview

Direct-mail letters selling home water treatment arrive in most mailboxes eventually, and they are written to be read quickly. This worksheet pairs one such letter, invented for the lesson, with the water data published by the town it targets, so students can test each claim against a source the letter itself never cites. The skill under practice transfers to any persuasive text: naming what a sentence asserts, naming what would prove it, and deciding whether the evidence offered does that job.

Does the Rowanfield Filter Letter Prove Its Claims? — Grade 10 English Language Arts
Name: ____________________________ Date: ______________

Student Worksheet

Read the two documents below. Both concern the fictional town of Melbeck. Then answer the questions.

Document 1: a letter mailed to Melbeck households by Rowanfield Home Water Systems

Dear Melbeck Resident,

Do you know what is in your tap water? Most families do not. Our whole-house system removes up to 99 percent of contaminants, and thousands of satisfied customers across the region already sleep better because of it.

Municipal water is treated to a legal standard, not to a health standard. Water can meet every rule and still carry chlorine, sediment, and hardness into your home. Our certified specialists have tested water in more than four hundred homes in this county. In many of them, the water left visible scale on fixtures.

The system installs in one day. Financing is available. Call before the end of the month and we will waive the installation fee, a savings of $850.

Sincerely, the Rowanfield team

Document 2: an excerpt from the Melbeck Water Department's annual water summary

  • Source: the Coldharbour River, at an intake three miles upstream of town.
  • Treatment: coagulation, filtration, disinfection, and pH adjustment.
  • Finished water turbidity, yearly average: 0.05 NTU. The federal limit for a plant of this type is 0.3 NTU.
  • Disinfectant residual leaving the plant, yearly average: 0.8 mg/L.
  • Hardness: 9 grains per gallon, which the department describes as hard water that can leave scale on fixtures and glassware.
  • Contaminants detected above a federal limit during the year: none.
  1. Write out the letter's central recommendation in one sentence of your own words.
  2. The letter opens with a question. What is the persuasive purpose of opening that way, rather than with a statement?
  3. Find the phrase "up to 99 percent." Explain what that phrase promises and what it does not promise.
  4. The letter says thousands of customers sleep better. Is that evidence for the product's performance? Explain your reasoning.
  5. The letter states that municipal water is treated to a legal standard rather than a health standard. Which document would a reader need in order to test that claim, and what in it is relevant?
  6. Find one claim in the letter that Document 2 supports. Quote the supporting line from Document 2.
  7. Find one claim in the letter that Document 2 does not support. Explain what Document 2 shows instead.
  8. The letter mentions testing in more than four hundred homes but reports no results from that testing. Explain why a reader should treat the sentence as weaker evidence than it sounds.
  9. Explain how the deadline and the waived fee work on a reader, and name the appeal they use.
  10. A neighbor says the letter must be accurate because none of its sentences are false. Explain why a set of true sentences can still mislead a reader.
  11. Write a short argument of six to eight sentences answering this question: does the Rowanfield letter give a Melbeck household enough evidence to buy the system? State a precise claim, support it with evidence from both documents, and explain your reasoning.

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: The letter recommends that Melbeck households buy and install a Rowanfield whole-house treatment system. Accept any paraphrase naming the purchase as the requested action.
  2. Answer: The question puts the reader in the position of not knowing, which creates a gap the product then fills. A statement would have to be defended, while a question only has to be answered, and the second sentence answers it on the reader's behalf.
  3. Answer: It promises a ceiling, not a result. A system removing two percent of one contaminant satisfies "up to 99 percent" exactly as well as one removing ninety-nine, and the phrase names no specific contaminant or test condition.
  4. Answer: No. Sleeping better is a report of customer feeling, not a measurement of what the system removes, and the letter gives no count, no source, and no way to check the number of customers.
  5. Answer: Document 2, the town's water summary, is the closest source. Its relevant lines are the statement that no contaminant was detected above a federal limit and the turbidity average of 0.05 NTU against a limit of 0.3 NTU. The letter already concedes that the water meets the rules, though, so fully testing its distinction between legal and health standards would need a source explaining how federal limits are set. Credit students who point out this limit.
  6. Answer: The claim about hardness and scale. Document 2 lists hardness of 9 grains per gallon and describes it as hard water that can leave scale on fixtures and glassware.
  7. Answer: The implication that the water carries sediment. Document 2 reports a yearly average turbidity of 0.05 NTU, far below the 0.3 NTU limit, which indicates clear water rather than visible sediment. Accept the chlorine claim if the student notes that a residual is deliberate and is reported as leaving the plant.
  8. Answer: A count of tests is not a result. The sentence borrows the authority of measurement while withholding every finding, and a reader cannot tell how many of the four hundred homes showed any problem at all.
  9. Answer: They compress the decision, so a reader who would otherwise gather more information acts before the deadline. The appeal is to urgency and to loss, since the reader is invited to think about what the delay costs rather than what the system does.
  10. Answer: Because selection, emphasis, and omission do the misleading. Each sentence can be defensible while the letter as a whole implies a problem the town's own data do not show, and the reader is left with a false picture assembled from true parts.
  11. Answer: Answers will vary. A proficient response states a precise claim, cites at least one specific line from the letter and one from Document 2, distinguishes the hardness claim the data support from the contamination claim they do not, and explains why the evidence is or is not sufficient for the purchase.

Differentiation

Support

Give these students the letter with each claim already numbered in the margin, and reduce the item set to 1, 3, 6, 7, and 11. Provide a two-column chart labeled "What the letter says" and "What the town data show" to complete before writing item 11.

Extension

Ask students to rewrite the letter so that every claim in it is supported by Document 2, then write a brief note explaining which selling points they had to drop and what that reveals about the original.

ELL supports

Pre-teach "claim," "evidence," "hedge," "turbidity," and "scale" with an example of hedged language from everyday speech. Provide sentence frames for items 6 and 7, such as "Document 2 supports the claim that ___ because it reports ___." Allow items 2, 9, and 10 to be answered orally.

Extensions

Have students bring in the packaging language from any filter product at home, such as a pitcher or a refrigerator cartridge, and mark every hedged phrase they find. Students then write one paragraph comparing the hedging in a product they own to the hedging in the Rowanfield letter.