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Worksheet Grade 10 English Language Arts

Two Drafts of the Mirefield Pond Fish Kill Explainer

A grade 10 revision worksheet comparing a vague first draft and a revised explainer about a fictional fish kill, with thirteen items on precision and support.

Objectives

  1. Students will state the controlling idea of an explanatory draft in one sentence.
  2. Students will identify a claim that a draft asserts without support.
  3. Students will explain what a definition and a mechanism add to an explanation.
  4. Students will revise a vague sentence so that it reports evidence.

Vocabulary

Dissolved oxygen
Dissolved oxygen is the oxygen gas mixed into water that fish and other underwater animals breathe. Cold, moving water holds more oxygen than warm, still water.

Also: controlling idea, mechanism, hedge, unsupported claim, revision

Teacher overview

This worksheet puts two drafts of the same short public explainer side by side so that students can name what a revision actually did. The subject is a fish kill in a park pond, which has a real mechanism a tenth grader can follow and a cause that the writers cannot yet prove. The misconception to name first is that revision means fixing grammar and swapping in stronger words. A second misconception is that adding a number makes writing more precise, which leads students to approve of the first draft's 90 percent figure without noticing that no source is attached to it.

Two Drafts of the Mirefield Pond Fish Kill Explainer — Grade 10 English Language Arts
Name: ____________________________ Date: ______________

Student Worksheet

Mirefield Pond, the parks department, and both drafts below are fictional, written for this worksheet. Read the two drafts, then answer questions 1 through 13.

Draft 1

Mirefield Pond Fish Kill

Last week a lot of dead fish showed up at Mirefield Pond and people were understandably upset. The pond has had problems before. Dissolved oxygen was low. Some say the fertilizer from the ball fields is to blame, and it is hard to argue with that. Warm weather makes things worse. About 90 percent of the fish in the pond were affected. The parks department is looking into it and will keep everyone posted. We appreciate your patience.

Draft 2

Why Fish Died at Mirefield Pond

Between Tuesday and Thursday of last week, park staff removed dead sunfish and bass from Mirefield Pond. The cause was low dissolved oxygen, which is the oxygen mixed into the water itself and taken in by fish through their gills. Most fish need dissolved oxygen above 5 milligrams per liter. Staff measured 2.1 milligrams per liter at dawn on Wednesday near the outlet, and 2.4 milligrams per liter at the same spot on Thursday.

Two conditions lowered the oxygen at the same time. Warm water holds less dissolved oxygen than cool water, and the pond reached its warmest reading of the summer that week. Algae had also spread thick across the surface after several weeks of runoff, and algae use oxygen at night instead of producing it. The dawn readings are the low point of the daily cycle for that reason.

Staff will continue dawn oxygen readings through September and will post the results at the boat ramp. Whether fertilizer from the ball fields is the main source of the nutrients that fed the algae has not been established, and the department has asked the county to sample the two inlet ditches.

Questions

  1. State the controlling idea of Draft 2 in one sentence.
  2. Quote the sentence in Draft 1 that comes closest to naming a cause.
  3. Explain what that sentence leaves out that Draft 2 supplies.
  4. Draft 1 uses the term "dissolved oxygen" without defining it. Quote the words Draft 2 adds to define it.
  5. Draft 2 removes the sentence about 90 percent of the fish. Give one reason a writer should not keep a number like that in a public explainer.
  6. Draft 2 reports each measurement with the place and the time it was taken. Explain what those details let a reader do that Draft 1 does not.
  7. Draft 1 says "Warm weather makes things worse." Quote the sentences in Draft 2 that replace this with a mechanism.
  8. Explain what the phrase "it is hard to argue with that" asks a reader to accept.
  9. Quote the sentence in Draft 2 that handles the fertilizer question without claiming more than the department can support.
  10. Draft 2 is written in three paragraphs. Name the job each paragraph does.
  11. Draft 1 ends with "We appreciate your patience." Explain why Draft 2's ending is more useful to a reader who lives near the pond.
  12. Draft 2 still contains one sentence a careful reader could question. Quote it, and write one sentence naming the evidence that would settle it.
  13. Rewrite this sentence from Draft 1 so that it reports evidence rather than a condition: "Dissolved oxygen was low."

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: Fish died at Mirefield Pond because dissolved oxygen fell well below the level fish need, and warm water together with a thick algae growth drove it down. Accept any sentence that names both the outcome and the oxygen cause.
  2. Answer: "Some say the fertilizer from the ball fields is to blame, and it is hard to argue with that." Accept "Dissolved oxygen was low" from students who argue that it names the immediate cause, provided they explain the choice.
  3. Answer: It leaves out who says it, what the fertilizer is supposed to have done, and any measurement. Draft 2 supplies the chain from runoff to algae to nighttime oxygen use, reports the oxygen readings, and states plainly that the fertilizer source has not been established.
  4. Answer: "which is the oxygen mixed into the water itself and taken in by fish through their gills."
  5. Answer: Accept any of these: the number has no source; no one is said to have counted the fish; a share of a fish population cannot be known without a population estimate; and a precise figure attached to nobody invites readers to trust the rest of the document more than the evidence supports.
  6. Answer: The details let a reader compare the two readings against the level fish need, see that both came from the same location, and understand that dawn is when oxygen is lowest. A reader can also judge whether the sampling was thorough, since two readings at one spot is a thinner record than readings across the pond.
  7. Answer: "Warm water holds less dissolved oxygen than cool water, and the pond reached its warmest reading of the summer that week. Algae had also spread thick across the surface after several weeks of runoff, and algae use oxygen at night instead of producing it." Accept either sentence alone for partial credit.
  8. Answer: It asks the reader to treat a claim as settled because objecting to it would feel unreasonable, rather than because evidence supports it. The phrase moves the burden onto anyone who disagrees while the writer supplies nothing.
  9. Answer: "Whether fertilizer from the ball fields is the main source of the nutrients that fed the algae has not been established, and the department has asked the county to sample the two inlet ditches."
  10. Answer: The first paragraph reports what happened and gives the immediate cause with measurements. The second explains the mechanism, meaning the two conditions that lowered the oxygen and why the dawn readings are lowest. The third says what happens next and marks the question that remains open.
  11. Answer: Draft 2's ending tells a reader what the department will do, when, and where the results can be found, and it names the open question honestly. Draft 1's ending asks for patience without saying what the reader is waiting for or how they would know when it arrives.
  12. Answer: Accept any reasonable choice with a matching evidence statement. Two strong answers are "The cause was low dissolved oxygen," which two readings at one spot support only weakly and which readings from several locations across the pond would settle, and "the pond reached its warmest reading of the summer that week," which needs the temperature record to confirm.
  13. Answer: Accept any rewrite that reports a measurement and its conditions, such as: "Staff measured dissolved oxygen at 2.1 milligrams per liter at dawn on Wednesday, well below the level most fish need." Do not credit rewrites that add a number the drafts do not provide.

Differentiation

Support

Give these students a copy with the two drafts printed in parallel columns and the sentences numbered in each, so items 2, 7, and 9 begin with matching rather than searching. Provide a two-column chart headed What Draft 1 says and What Draft 2 adds, and allow items 3, 6, and 11 to be answered in two sentences using supplied frames.

Extension

Ask these students to write the third draft the department would publish two weeks later, after the county returned results from the two inlet ditches showing that one ditch carried far more nutrients than the other. The draft must revise the open question from Draft 2 without claiming the fertilizer case is closed, and it must keep the mechanism paragraph intact.

ELL supports

Pre-teach dissolved oxygen, algae, runoff, outlet, and establish with a labeled sketch of the pond, the ball fields, and the two inlet ditches. Provide a bilingual glossary and allow items 5, 8, and 11 to be answered first as a short list of reasons. Item 13 may be completed by choosing from three supplied rewrites and explaining the choice.

Extensions

Have students locate a short public notice from a city department, a school, or a utility and mark every sentence that reports evidence, every sentence that makes a claim without it, and every sentence that does neither. Ask them to rewrite the weakest paragraph and to note what information they would have to obtain before the rewrite could be published.