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Lesson plan Grade 10 English Language Arts

Should Heron Lake Farms Face New Runoff Limits? An Argument Lesson

A grade 10 argument writing lesson on whether farms near a fictional lake should face new fertilizer runoff limits, using dissolved oxygen and fish-health evidence.

Objectives

  1. Students will state a precise claim on a contested local water-policy question.
  2. Students will support a claim with relevant evidence, including a real water-quality benchmark.
  3. Students will address a counterclaim and explain why their position still stands.

Vocabulary

Algal bloom
An algal bloom is a fast, thick growth of algae that can turn a lake green and scummy. Blooms happen when the water gets lots of nutrients and warm sunshine, and some blooms make toxins.
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: nutrient pollution, counterclaim, runoff

Teacher overview

Heron Lake, a fictional reservoir used for this lesson, has developed thick green algal blooms in the past three summers, and the town council is debating whether to require farms along the lake's inflow streams to plant wider buffer strips and cut back on fertilizer application near the water. This is a genuinely contested local question: farmers rely on fertilizer for their livelihood, while lake users worry about fish kills and swimming closures. The lesson gives students a short, two-sided evidence handout and asks them to write an argument paragraph that states a clear claim, supports it with specific evidence, and directly addresses a counterclaim, the structure grade 10 argument writing requires. A common misconception in early drafts is treating a counterclaim as something to mention and dismiss in a single dependent clause; the lesson pushes students to give the opposing view a real sentence of its own before rebutting it.

Procedure

Hook (5 min): Show students a simple two-column list on the board: "Green water" and "Empty fields." Ask which one worries them more and why, then explain that today's lesson is about a real tradeoff behind that choice.

Direct instruction (12 min): Distribute the evidence handout (Student Handout). Read it aloud, then model turning one piece of evidence into an argument sentence: "Because most fish need dissolved oxygen above 5 mg/L to survive, and algal blooms can strip oxygen from a lake as they die and decompose, the council should treat repeated blooms as a threat to Heron Lake's fish population." Explain that a strong counterclaim sentence states the opposing view fairly, in its own words, before the writer explains why it does not outweigh their claim.

Guided practice (15 min): In pairs, students identify which pieces of evidence on the handout best support each side (farmers' costs versus lake health), then draft one counterclaim-and-rebuttal pair together: a sentence stating the strongest opposing point, followed by a sentence explaining why their claim still holds.

Independent practice (18 min): Each student writes an argument paragraph of at least 150 words: a claim on whether Heron Lake should adopt the new runoff limits, at least two pieces of evidence from the handout, one counterclaim stated fairly, and a rebuttal.

Closure / exit ticket (5 min): Students underline their own claim sentence and their own counterclaim sentence in two different colors, then hand in their paragraph. Scan a sample of submissions for a genuine, fairly stated counterclaim (not just "some people disagree") before dismissal.

Should Heron Lake Farms Face New Runoff Limits? An Argument Lesson — Grade 10 English Language Arts
Name: ____________________________ Date: ______________

Student Handout

Evidence file: the Heron Lake runoff question

For new limits on fertilizer application near the lake:

  • Most fish need dissolved oxygen above 5 mg/L to survive, and cold water holds more oxygen than warm water. When an algal bloom dies off, the bacteria that decompose it consume large amounts of oxygen, which can push levels below what fish need.
  • A fictional resident survey conducted for this lesson found that lakefront property owners report fewer weeks of safe swimming each summer since the blooms began, a pattern residents connect to increased fertilizer use upstream.
  • Wider buffer strips of unfertilized plants between farm fields and the water are a commonly recommended way to filter nutrients out of runoff before it reaches a lake.

Against new limits on fertilizer application near the lake:

  • Agriculture accounts for roughly 70% of global freshwater withdrawals, a reminder that farming is central to how water gets used everywhere, and local farmers argue that a new ordinance treats them as the sole cause of a problem with many contributing sources.
  • A fictional farm-bureau representative created for this lesson argues that buffer strips take productive land out of use permanently, cutting into a farm's income in a year when crop prices are already low.
  • Runoff also comes from lawns, golf courses, and storm drains around the lake, not only from farm fields, so some residents question whether farms should bear the ordinance's cost alone.

Questions

  1. What four parts must your argument paragraph contain?
  2. According to the evidence file, how can an algal bloom threaten Heron Lake's fish?
  3. Write one counterclaim sentence that states the opposing view fairly, followed by your rebuttal.

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: A claim, at least two pieces of supporting evidence, a counterclaim, and a rebuttal.
    These are the four components the lesson asks every paragraph to contain, matching the structure required by grade 10 argument writing.
  2. Answer: Because oxygen drops when the bacteria that decompose a dying algal bloom consume it, which can push levels below the 5 mg/L most fish need.
    The handout's first "for" point connects the bloom's die-off directly to the dissolved-oxygen threshold, giving students a specific causal chain to cite.
  3. Answer: Answers will vary, but a strong response states the opposing view in a full, fair sentence (not a dismissive fragment) before explaining why the writer's claim still stands.

Differentiation

Support (below grade level)

Provide sentence frames for each required part ("Heron Lake should/should not ___ because ___." / "Some farmers argue ___, but ___.") and reduce the required word count to 100 while keeping all four structural parts.

Extension (above grade level)

Ask students to add a second counterclaim, drawn from the "against" evidence they did not use in their first draft, and explain why they chose to rebut one counterclaim over the other in their final paragraph.

ELL supports

Pre-teach "nutrient pollution," "algal bloom," "dissolved oxygen," and "counterclaim" with simple definitions and a labeled before/after image of a clear lake and a bloom-covered lake. Allow the counterclaim-and-rebuttal pair in guided practice to be drafted orally with a partner before either student writes it down.