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Quiz & test questions Grade 7 Social Studies & Civics

Cattail Creek Pollution and Policy: A Grade 7 Quiz

A grade 7 quiz on point and nonpoint water pollution in a fictional watershed, mixing multiple-choice, short-answer, and percent items with a policy question.

Objectives

  1. Students will distinguish point-source from nonpoint-source water pollution.
  2. Students will calculate percent reductions and shares of a creek's pollution load.
  3. Students will explain why point sources are easier to regulate than nonpoint sources.

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.
Watershed
A watershed is all the land where rain that falls will drain to the same stream, river, or lake. Everyone lives in a watershed, no matter how far from the water they live.

Also: point source, nonpoint source, Clean Water Act

Teacher overview

This 30-minute quiz is worth 25 points and checks whether students can tell point-source from nonpoint-source pollution, calculate percent reductions and shares of a pollution load, and explain why the two kinds of pollution are regulated differently. It uses the fictional Cattail Creek watershed and mixes two multiple-choice items, two short-answer items, and four computation items.

Cattail Creek Pollution and Policy: A Grade 7 Quiz — Grade 7 Social Studies & Civics
Name: ____________________________ Date: ______________

Assessment

  1. (2 points) A single pipe carries wastewater from one factory directly into Cattail Creek. This is an example of what kind of pollution source?
    • A) Nonpoint source
    • B) Point source
    • C) Groundwater source
    • D) Natural source
  2. (2 points) Fertilizer washing off many different farm fields after a rainstorm is an example of what kind of pollution source?
    • A) Point source
    • B) Nonpoint source
    • C) A single source
    • D) Not pollution
  3. (3 points) In one or two sentences, explain one reason nonpoint pollution is harder to control than point pollution.
  4. (4 points) The factory's pipe releases 400 pounds of pollution into Cattail Creek each month. A new filter removes 75 percent of it. How many pounds does the filter remove each month? Show your work.
  5. (3 points) After the filter removes 75 percent, how many pounds of pollution still reach the creek each month?
  6. (4 points) Most fish need dissolved oxygen above 5 mg/L. One summer, Cattail Creek measures 4 mg/L. How much would the dissolved oxygen need to rise to reach the 5 mg/L level fish need?
  7. (3 points) Under the Clean Water Act, the factory must have a permit to release pollution from its pipe. In one or two sentences, explain why a permit for the factory's pipe is easier to enforce than rules for farm runoff.
  8. (4 points) Cattail Creek's pollution comes from two sources each month: 400 pounds from the factory pipe and 600 pounds from farm runoff, for 1,000 pounds in total. What percent of the total comes from the factory pipe? Show your work.

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: B) Point source.
    A point source is pollution that enters water from one clear spot, such as a single pipe, so the factory's pipe is a point source.
  2. Answer: B) Nonpoint source.
    Runoff from many scattered fields does not come from one spot, so it is nonpoint-source pollution.
  3. Answer: Nonpoint pollution comes from many scattered places at once, such as fields, lawns, and roads, so there is no single pipe to inspect or shut off. This makes it harder to measure and control than pollution from one identified source.
  4. Answer: 300 pounds.
    75 percent of 400 pounds is 0.75 × 400 = 300 pounds removed each month.
  5. Answer: 100 pounds.
    400 pounds − 300 pounds removed = 100 pounds still reaching the creek each month.
  6. Answer: 1 mg/L.
    The creek needs to reach 5 mg/L and measures 4 mg/L, so it must rise 5 − 4 = 1 mg/L.
  7. Answer: The factory's pollution comes from one known pipe, so inspectors can measure exactly what leaves it and hold one owner responsible. Farm runoff comes from many properties at once, so there is no single pipe or owner to check, which makes a permit far harder to enforce.
  8. Answer: 40 percent.
    The factory pipe adds 400 pounds out of 1,000 pounds total, and 400 ÷ 1,000 = 0.40 = 40 percent.

Differentiation

Support (below grade level)

Provide a labeled picture of the watershed showing the factory pipe and the farm fields, and give a reminder card that "percent means out of 100." Set up the calculations for items 4 and 8 (0.75 × 400 = ___ and 400 ÷ 1,000 = ___) and allow calculators.

Extension (above grade level)

Ask students to calculate the creek's total monthly pollution after both the factory filter (removing 75 percent of the factory's 400 pounds) and a new buffer strip that cuts farm runoff by half, then find the percent by which the creek's total pollution has dropped.

ELL supports

Pre-teach "point source," "nonpoint source," "dissolved oxygen," "Clean Water Act," and "watershed" with simple images (one pipe versus many fields draining to a creek). Allow the short-answer items to be completed with a provided sentence frame, such as "Nonpoint pollution is harder to control because ___."

Extensions

Have students find one real rule or program their state uses to reduce farm or road runoff, using a state environmental agency website, and write two sentences on how it tries to solve the nonpoint-source problem this quiz describes.