Seaweed Solutions

Overview

Students read selected sections of Kate Evans’s information text Seaweed Solutions and explain how seaweed may reduce methane from farm animals. They practise retrieving evidence, working out word meanings from context, and asking and answering open-ended “why” and “how” questions.

Learning intentions

• WALT identify the main ideas and key details in an information text.
• WALT work out the meaning of unfamiliar words using context and the glossary.
• WALT answer “what”, “when”, “why”, and “how” questions using evidence.
• WALT ask research questions connected to an environmental issue.

Success criteria

• I can explain the main problem described in the text.
• I can give meanings for eight unfamiliar words.
• I can answer questions in complete sentences and include page evidence.
• I can ask two useful questions for further research.

Curriculum links

• Oral Language Practices — Communicating and Presenting: asking and answering why and how questions to explain ideas.
• Oral Language Knowledge — Communicating and Presenting: recognising that questions often begin with who, what, where, when, why, or how.
• Oral Language Knowledge — Communicating and Presenting: understanding that “how” questions explain how something works, happens, or is done.
• Oral Language Knowledge — Communicating and Presenting: using open-ended questions to encourage extended thinking and elaboration.

Lesson structure (30 minutes)

1. 0–4 min · Hook and prediction. Teacher displays the opening question on the hook and prediction slide: “Could seaweed help cows and sheep reduce climate change?” Students discuss what they already know, then make one prediction with a partner.

2. 4–8 min · First read and model. Teacher reads pages 33–34 aloud, briefly modelling how to pause at an unfamiliar word and use nearby clues. Students follow the text, underline one key fact, and identify the problem facing ruminants.

3. 8–14 min · Vocabulary investigation. Teacher distributes the vocabulary and comprehension worksheet and models the word “ruminant” using the sentence and glossary. In pairs, students find the meanings of the eight selected words below, using context and the glossary; they may also use the vocabulary morphology cards to discuss word parts where useful.

4. 14–23 min · Evidence hunt. Teacher uses the question and evidence slides to display the comprehension questions. Students answer the ten questions independently first, then compare answers with a partner and add page numbers as evidence. Teacher circulates, prompting students to locate the exact sentence or paragraph rather than guess.

5. 23–27 min · Explain and extend. Teacher selects three questions, including one “why” and one “how”, for whole-class discussion. Students share answers using the frame: “I think ___ because the text says ___ on page ___.” Class identifies which answers require retrieval and which require explanation or inference.

6. 27–30 min · Research questions and exit check. Teacher displays the research and reflection slide. Students write two questions they would research about seaweed, methane, farming, or climate change, then complete the worksheet reflection: “One important idea I learned was …”

Vocabulary: find the meaning

Students write a student-friendly meaning and, where possible, use the word in a sentence.

1. ruminant
2. microbes
3. methane
4. emissions
5. agriculture
6. bromoform
7. carcinogen
8. breeding

Suggested answers:

1. Ruminant — an animal such as a cow or sheep with a specialised stomach that digests grass. (p. 33)
2. Microbes — tiny living things that can usually only be seen through a microscope. (p. 33; glossary p. 38)
3. Methane — a gas produced during digestion that contributes to greenhouse gas emissions. (p. 33)
4. Emissions — gases released into the air. (p. 33)
5. Agriculture — farming animals and growing crops for food and other products. (p. 38)
6. Bromoform — a chemical in Asparagopsis that reduces the methane an animal produces. (p. 36)
7. Carcinogen — something that can cause cancer. (p. 37; glossary p. 38)
8. Breeding — choosing which animals mate in the hope that their offspring have certain qualities. (p. 38)

Comprehension questions, answers, and page evidence

1. What do cows and sheep produce when microbes break down grass in the rumen? Answer: They produce methane. (p. 33)

2. Why is methane from cows and sheep a problem for New Zealand? Answer: Their burps contribute around half of New Zealand’s greenhouse gas emissions. (p. 33)

3. What and how did the Canadian farmer notice about the cows beside the beach? Answer: They produced more milk and ate a lot of washed-up seaweed. (p. 34)

4. How did Robert Kinley test whether seaweed made a difference? Answer: He compared the cows’ burps and tested different seaweeds in a laboratory and with cows and sheep. (p. 34)

5. Why did Asparagopsis stand out from the other seaweeds? Answer: It reduced methane burped by cows and sheep by up to 90 percent, even in small amounts. (p. 34)

6. What happens to the young seaweed plants in the Bluff tanks? Answer: They are kept moving so they receive equal light and double in size every ten to twelve days. (p. 34)

7. How is the seaweed changed from a water-filled crop into animal feed? Answer: The water is removed, the seaweed is dried, and it is then ready to feed to animals. (p. 36)

8. Why does bromoform reduce methane emissions? Answer: It reduces the amount of methane an animal produces in its stomach, resulting in fewer methane burps. (p. 36)

9. What are two challenges to using Asparagopsis on New Zealand farms? Answer: It is difficult to give the product to mostly grass-fed animals, and the government has not approved bromoform for use. (p. 37)

10. How could scientists try to reduce methane if seaweed is not the only solution? Answer: They could develop a vaccine, breed lower-methane animals, or use UV light to increase the fat content of grass. (p. 38)

Research questions

• How much methane do New Zealand farms produce compared with other greenhouse gases?
• What are the possible benefits and risks of feeding Asparagopsis to cows and sheep?

Resources

• Student copies of Seaweed Solutions, pages 33–38
• the complete 30-minute teaching slide deck
• the vocabulary and comprehension worksheet
• the vocabulary morphology cards
• Highlighters or coloured pencils
• Pens or pencils
• Board or display screen

Assessment

• Listen for students explaining word meanings using context, the glossary, or evidence from the text.
• Check whether comprehension answers are accurate, complete, and supported by correct page numbers.
• Collect the worksheet and assess whether each student has written two relevant, open-ended research questions.

Differentiation

• Support readers with a partner, teacher-guided reading of pages 33–34, a glossary, and sentence starters: “The text explains … because …” and “On page … it says …”.
• Provide a reduced choice of four vocabulary words for students who need a smaller initial task, then add further words if ready.
• Allow students to dictate answers, use speech-to-text, or record oral answers where writing is a barrier.
• Extend confident readers by asking them to classify each comprehension question as retrieval, inference, or explanation and justify their choice.