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Classroom activity Grade 4 English Language Arts

Expert Groups at the Morrowfield Treatment Lagoon

A grade 4 jigsaw in which four expert texts about a fictional treatment lagoon are taught back to home groups, then combined into a short research answer.

Objectives

  1. Students will read one assigned text closely and answer two questions from its details.
  2. Students will teach their assigned text to three classmates who did not read it.
  3. Students will combine four sources into a written answer to one research question.

Vocabulary

Key words: lagoon, microbe, oxygen, settle, sample

Teacher overview

This is a four-way jigsaw for a class that can be divided into home groups of four. Each student reads one of four short expert texts about a fictional treatment lagoon outside the town of Morrowfield, meets with the other students who read the same text, and then returns to teach it, so no home group can answer the research question until all four members have reported. Many fourth graders picture wastewater cleaning as a straining or filtering job, and the texts are written to correct that: the work at a lagoon is done by living things eating waste, and the equipment mostly keeps those living things supplied with air. The activity ends with each student writing the combined answer in their own words.

Activity Directions

  1. Before class, copy the Student Handout for every student and post the four expert-group signs in four corners. Write the research question on the board where it stays visible: How does Morrowfield use living things to clean its used water?
  2. Form home groups of four and letter the members A, B, C, and D. In a class that does not divide evenly, give one group a fifth member who shares text D.
  3. Read the handout's opening paragraph aloud to the whole class so everyone starts with the same picture of the lagoon, then send students to the corner matching their letter.
  4. Expert round, fifteen minutes: students read only their assigned text in their corner, then answer the two numbered items for that text. Members compare answers inside the corner and settle any disagreement by pointing at a line in the text.
  5. Send students back to their home groups. Teaching round, sixteen minutes: A teaches first, then B, C, and D, four minutes each. The three listeners fill in that row of the chart while the expert talks. The expert may show the text but may not simply hand it over to be read.
  6. Circulate during the teaching round and ask at least one listener in each group to restate what the expert just said before the next expert begins.
  7. Stop the teaching round when every group has all four chart rows filled. Give students eight minutes alone to write items 9 and 10.
  8. Debrief with two questions. First, ask which expert text was hardest to teach without letting the group read it, and why. Second, ask what would happen at the lagoon if the paddle wheels stopped for a week, and press students to answer using text C rather than a guess.
Expert Groups at the Morrowfield Treatment Lagoon — Grade 4 English Language Arts
Name: ____________________________ Date: ______________

Student Handout

The Morrowfield lagoon is made up for this activity. Morrowfield is a small town whose used water flows to three shallow ponds in a row outside of town, together called a treatment lagoon. Water sits in the lagoon for weeks before it moves on. Read only the text with your letter.

Text A: What arrives at the lagoon. Every sink, shower, and toilet in Morrowfield drains into one pipe that ends at the lagoon. The water that arrives is cloudy and grey. It carries food scraps, soap, paper, and waste from homes. Heavy bits sink to the bottom of the first pond within a day. The water that stays on top still holds waste too small to see. That hidden waste is the part the lagoon has to remove.

Text B: The living workers. The lagoon is full of microbes, which are living things far too small to see without a microscope. Nobody trucks them in. They arrive with the water and then multiply, because the lagoon is full of the food they eat. Those microbes eat the waste that is dissolved in the water. As they eat, they grow and divide, and clumps of them sink slowly to the lagoon floor. The town does not add a chemical to break down that waste. Living things do the work.

Text C: Why the paddles run. Microbes that eat waste quickly need oxygen, the same gas people breathe. In still water full of waste, the microbes use up oxygen faster than air can replace it. Morrowfield keeps four paddle wheels turning at the surface of the middle pond, and each wheel throws water into the air in a wide arc. Air mixes into the water as it splashes back down. When the paddles stop for repairs, the water starts to smell within a day or two, because the fastest microbes run short of oxygen.

Text D: The last check. Water leaves the third pond through a gate and flows into Tibbet Creek. Before the gate opens each week, an operator fills a bottle at the outlet and carries it to a small lab. She checks whether the water is clear, whether it smells, and how much oxygen it holds. The results go in a log the state can ask to see. If a test comes back poor, the gate stays shut and the water is held for another week.

Home group chart. Fill in one row while each expert teaches.

Text Expert's letter The one big idea of this text One detail I want to remember
A. What arrives at the lagoon
B. The living workers
C. Why the paddles run
D. The last check

Answer the two items for your text.

  1. Text A: Name three things the arriving water carries from homes.
  2. Text A: The text says heavy bits sink within a day. What can you tell about why the lagoon still needs the later ponds?
  3. Text B: Where do the microbes in the lagoon come from?
  4. Text B: The text says the town adds no chemical. What can you tell about what does the cleaning work?
  5. Text C: What do the paddle wheels put into the water?
  6. Text C: The text says the water smells within a day or two when the paddles stop. What can you tell about the microbes at that point?
  7. Text D: What three things does the operator check in the sample?
  8. Text D: What happens when a test comes back poor?
  9. Use all four rows of your chart. Write two sentences that answer the research question: How does Morrowfield use living things to clean its used water?
  10. Write one new question about the lagoon that none of the four texts answers.

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: Food scraps, soap, paper, and waste from homes. Accept any three of those four items, all listed in text A.
  2. Answer: Because waste too small to see is still dissolved in the water after the heavy bits sink. Accept any answer that names the hidden or dissolved waste as the reason the water moves on.
  3. Answer: They arrive with the water itself and then multiply in the lagoon. Text B states that nobody trucks them in.
  4. Answer: The microbes do the cleaning work by eating the dissolved waste. Accept any answer naming the living things rather than equipment or chemicals.
  5. Answer: Air, and with it the oxygen the microbes need. Text C states that air mixes in as the thrown water splashes back down.
  6. Answer: The fastest microbes are running short of oxygen, so the waste is not being eaten as quickly. Accept any answer that connects the smell to the missing oxygen.
  7. Answer: Whether the water is clear, whether it smells, and how much oxygen it holds. Text D lists all three.
  8. Answer: The gate stays shut and the water is held for another week. Text D states this directly.
  9. Answer: Accept any two sentences that name microbes as the workers and name at least one thing the town does to keep them working, such as running the paddle wheels for oxygen or holding the water for weeks. A proficient response also mentions the final check before the gate opens.
  10. Answer: Accept any question the four texts do not answer, such as how long the water stays in each pond, what happens to the clumps on the lagoon floor, or who reads the log the operator keeps.

Differentiation

Support

Assign these students text A or text C, the two shortest, and highlight the sentence that answers each of their two items before the expert round begins. Give them a two-sentence script for the teaching round so they know exactly what to say to their home group.

Extension

Ask these students to write a fifth expert text for the same lagoon, about what happens to the clumps that settle on the pond floor, and to add two items in the same style. Their text must not contradict anything in texts A through D.

ELL supports

Pre-teach lagoon, microbe, oxygen, and settle with a picture of three ponds in a row and a jar of cloudy water left to stand. Allow the teaching round to be done with the chart plus gestures at first, and let students write items 9 and 10 in short phrases before expanding them into sentences.

Extensions

Invite students to compare the lagoon in these texts with a treatment plant that uses tanks instead of ponds, listing what stays the same about the living workers and what changes about the equipment. Keep the list to the information in the four texts plus whatever the class can find in one classroom source.