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Worksheet Grade 8 English Language Arts

Anecdote or Data? Evidence Types in the Rissley Dam Debate

Grade 8 students classify six pieces of evidence about a fictional mill dam by type, then judge which ones actually support each side's claim and why.

Objectives

  1. Students will classify evidence as anecdote, single measurement, multi-year record, expert inspection, or outside example.
  2. Students will explain one limit of a single measurement used to describe a river.
  3. Students will match a claim to the evidence that supports it most directly.

Vocabulary

Fish ladder
A series of water steps built beside a dam so migrating fish, like salmon, can swim past it. Fish leap or swim from pool to pool to reach the river above.

Also: anecdote, single measurement, multi-year record, expert inspection, outside example

Teacher overview

Six pieces of evidence about a fictional mill dam are printed on this worksheet, and students sort them by type before deciding which ones actually bear on each side's claim. The town of Rissley, its dam, and its river are invented, and every figure in the evidence belongs to that invented scenario. The misconception this worksheet is built to catch is the belief that evidence is strong whenever it is specific: students routinely rank a single dated measurement above a fifteen-year record because the single measurement sounds more exact. Evidence E exists to make that error visible, and the debrief should return to it after item 6.

Anecdote or Data? Evidence Types in the Rissley Dam Debate — Grade 8 English Language Arts
Name: ____________________________ Date: ______________

Student Worksheet

The situation. The town of Rissley owns a small mill dam on the Craywood River. The council is deciding between two claims.

  • Claim 1. Rissley should remove the mill dam.
  • Claim 2. Rissley should keep the mill dam and repair its spillway.

Six pieces of evidence were submitted to the council. Each one is labeled with a letter.

Evidence A. "My grandfather fished below the dam every spring. He always said the shad runs stopped coming after 1961."

Evidence B. "The county has counted fish passing the Craywood River fish ladder every April since 2009. The count rose in six of those years and fell in nine."

Evidence C. "A licensed dam safety engineer inspected the spillway in March and rated the condition of its concrete as poor."

Evidence D. "The town of Trenmore removed a similar mill dam in 2016. Its riverfront park now draws visitors from across the county."

Evidence E. "One water sample taken above the dam on August 3 measured dissolved oxygen at 4.1 mg/L."

Evidence F. "The Rissley dam produces about 180 kilowatts, which is roughly enough for 120 homes in town."

Use these five labels for items 1 through 5: anecdote, single measurement, multi-year record, expert inspection, outside example.

  1. Which label fits Evidence A? Give the label and one reason for your choice.
  2. Which label fits Evidence B? Give the label and one reason for your choice.
  3. Which label fits Evidence C? Give the label and one reason for your choice.
  4. Which label fits Evidence D? Give the label and one reason for your choice.
  5. Which label fits Evidence E? Give the label and one reason for your choice.
  6. Evidence E reports one sample on one day. Explain one limit of using it to describe the river as a whole.
  7. Which piece of evidence gives the strongest support for Claim 2? Copy it and explain the link in one sentence.
  8. Evidence A and Evidence B both concern fish. Explain why B is the stronger support for a statement about fish numbers.
  9. Evidence D describes a different town. Write one question you would need answered before using D to support Claim 1.
  10. Evidence F supports Claim 2. Name one thing you would need to know in order to judge how much weight F deserves.
  11. Rank Evidence B, C, and F from strongest to weakest support for Claim 2. Explain your first choice in two sentences.
  12. Write a claim of your own about the Rissley dam. Pair it with the single piece of evidence from A through F that fits it best, and explain the fit in one sentence.

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: Anecdote. It reports one person's remembered experience rather than a record anyone else could check.
  2. Answer: Multi-year record. It reports counts taken the same way every April across fifteen years, so it shows a pattern rather than a moment.
  3. Answer: Expert inspection. A licensed engineer examined the structure and issued a rating based on training and a defined standard.
  4. Answer: Outside example. It reports what happened in another town and invites the council to reason from that case to this one.
  5. Answer: Single measurement. It reports one number from one sample taken on one date at one spot.
  6. Answer: Accept any answer naming a real limit. One sample cannot show change over a day or a season, and dissolved oxygen swings between afternoon and dawn and between summer and spring, so a single August reading may not describe the river in April.
  7. Answer: Evidence C. The engineer's poor rating of the spillway concrete is the reason repair work is needed, and Claim 2 is the claim that calls for repairing the spillway. Also accept Evidence F if the student explains that the power it produces is the reason to keep the dam rather than remove it.
  8. Answer: Evidence B rests on counts taken the same way every year, so it can be checked and compared. Evidence A rests on one person's memory of a change more than sixty years ago, with no count behind it.
  9. Answer: Accept any question about how well Trenmore matches Rissley. Strong versions ask whether the two dams were similar in size or condition, whether the two rivers carry similar flow, or whether Trenmore spent money on the park that Rissley would also have to spend.
  10. Answer: Accept any answer naming information the card leaves out. Useful examples include how many days per year the dam actually generates, what the electricity earns or saves, and what the repair would cost against that amount.
  11. Answer: C, then F, then B. Evidence C is the strongest because a poor spillway rating is the direct reason to fund a repair. Evidence F gives a benefit worth keeping but no cost to weigh it against, and Evidence B is about fish rather than about the dam's condition or value. Accept F above C only if the student argues the generation figure establishes why the dam is worth repairing at all.
  12. Answer: Accept any clear claim paired with evidence that bears on it directly. A model response: "Rissley should repair the spillway before the next spring flood, because Evidence C reports that a licensed engineer rated the concrete as poor in March."

Differentiation

Support

Cut the six evidence cards apart and have students physically sort them under the five labels before writing anything, then complete only items 1 through 8. Model item 1 aloud, thinking through why a remembered story cannot be checked, so the difference between anecdote and record is established before students work alone.

Extension

Ask students to write a seventh piece of evidence that would genuinely change the ranking they gave in item 11, then explain in a paragraph what makes their new evidence stronger than the card it displaces.

ELL supports

Provide a five-card reference set with each evidence type named, defined in one line, and shown with a short example unrelated to dams. Allow students to answer items 1 through 5 with the label plus a short phrase rather than a full sentence, and provide the frame "Evidence ___ is stronger than Evidence ___ because ___" for items 8 and 11.

Extensions

Have students write the two-paragraph council decision that follows from their ranking in item 11, naming which evidence they relied on and which they set aside, and explaining why the evidence they set aside did not settle the question.