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Lesson plan Grade 7 Art & Music

Fertilizer as Feed and Pollutant: A Nutrient Infographic Lesson

A grade 7 art lesson where students design a two-panel infographic showing how a fictional farm's nitrogen both feeds crops and pollutes a lake.

Objectives

  1. Students will design a two-panel infographic showing nitrogen as both a crop nutrient and a pollutant.
  2. Students will compute pounds and percentages of nitrogen used and lost from given data.
  3. Students will explain why the same nutrient can help crops and harm a lake.

Vocabulary

Key words: nutrient, nitrogen, runoff, algae bloom, infographic

Teacher overview

Nitrogen is a nutrient that plants need, which is why farmers add it as fertilizer. When more nitrogen is applied than crops can use, the extra washes off fields into lakes and rivers, where it feeds heavy algae growth that can choke out fish. This lesson asks students to design a two-panel infographic that holds both truths at once: one panel shows nitrogen feeding crops, the other shows the same nitrogen polluting a lake. Students use data from the fictional Quill Hollow Farm and nearby Teal Lake. A common misconception this lesson corrects is that a substance is either useful or harmful; nitrogen is a clear case where the amount and the place decide which role it plays.

Procedure

Hook (10 min): Ask students to name something that is helpful in one amount and harmful in another. Steer the discussion toward the idea that quantity and location change whether something is good or bad, then introduce nitrogen as that kind of substance for water.

Direct instruction (15 min): Review the two roles of nitrogen and the parts of a strong infographic: a clear title, two labeled panels, one number made large, and a short caption. Model the math with a teacher example that differs from the handout. Suppose a field receives 200 pounds of nitrogen and the crops take up 70 percent. Show that 70 percent of 200 is 140 pounds used, leaving 60 pounds to run off. Sketch how that 60 pounds could become the big number on the pollution panel.

Guided practice (15 min): Using the Quill Hollow data sheet, students complete the handout calculations, then decide which single number belongs in large type on each panel.

Independent practice (10 min): Students lay out their two panels on grid paper, place the chosen numbers, and write one short caption per panel explaining the role nitrogen plays there.

Closure / exit ticket (5 min): Students answer one question on a card: in one sentence, why can the same nitrogen help a cornfield and hurt a lake? Scan the cards for the idea that the amount and location decide the effect; reteach if most students do not state it clearly.

Fertilizer as Feed and Pollutant: A Nutrient Infographic Lesson — Grade 7 Art & Music
Name: ____________________________ Date: ______________

Student Handout

Suppose the fictional Quill Hollow Farm applies 400 pounds of nitrogen this spring. The corn takes up 65 percent of it. The rest washes into Teal Lake. Use these numbers for questions 1 through 6.

  1. How many pounds of nitrogen do the crops take up?
  2. How many pounds of nitrogen run off into Teal Lake?
  3. What percent of the applied nitrogen runs off?
  4. The next year the farmer applies only 300 pounds, and crops again take up 65 percent. How many pounds run off that year?
  5. The runoff dropped from 140 pounds to 105 pounds. By what percent did the runoff amount decrease?
  6. Your pollution panel shows runoff as a share of a 10-square bar. How many squares should be shaded to show 35 percent?

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: 260 pounds.
    65 percent of 400 is 0.65 times 400, which equals 260 pounds taken up by crops.
  2. Answer: 140 pounds.
    400 pounds applied minus 260 pounds used equals 140 pounds of runoff.
  3. Answer: 35 percent.
    140 pounds of runoff divided by 400 pounds applied equals 0.35, or 35 percent.
  4. Answer: 105 pounds.
    65 percent of 300 is 195 pounds used, so 300 minus 195 equals 105 pounds of runoff.
  5. Answer: 25 percent.
    The drop is 140 minus 105, which is 35 pounds; 35 divided by 140 equals 0.25, a 25 percent decrease.
  6. Answer: 3.5 squares.
    35 percent of 10 squares is 0.35 times 10, which equals 3.5 shaded squares.

Differentiation

Support

Provide the first calculation worked out and the rest set up as fill-in steps (0.65 times 400 equals ___). Give a template with the two panels and the bar already outlined so students focus on the numbers and captions.

Extension

Ask students to add a third small panel showing what happens if the farmer uses a cover crop that cuts runoff in half, and to compute the new runoff pounds and its percent of the applied nitrogen.

ELL supports

Pre-teach "nutrient," "runoff," and "algae bloom" with a labeled picture of a field, a lake, and green water. Allow captions to be short phrases, and provide a sentence frame: "Here nitrogen ___ because ___."