Handbook-informed classroom practice
Explain gas exchange without losing meaning
A 45-minute writing lesson connecting four original routines with an individual transfer task.
The lesson’s worked models
Turn a Leaf Diagram into a Paragraph
“Carbon dioxide can enter through stomata and oxygen can leave. Water vapour can also leave through these openings.” The diagram supports directions of movement; it does not establish a measured rate.
Stoma
Carbon dioxide in; oxygen out
Water vapour out
Retain a Condition in a Summary
Original: “Stomata may close when water is scarce, reducing water loss but also restricting carbon dioxide entry.” Summary: “Closing stomata in dry conditions can reduce water loss and carbon dioxide entry.”
Water is scarce
Stomata may close
Less water loss and CO₂ entry
Repair an Unhelpful Peer Comment
Vague: “Add more detail.” Useful: “Explain how closing the opening affects movement of water vapour; keep your dry-condition phrase.”
The closing sentence
Link closing to water loss
The dry-condition phrase
Fade a Gas-Exchange Frame
Full support: “When __, the stomata may __, so __.” Lighter support: condition · opening · consequence. Independent response must still explain the relationship.
Full sentence frame
Three planning words
Own accurate wording
A 45-minute route
Start · 5 minutes: introduce the subject context, establish vocabulary and show the first model.
- Turn a Leaf Diagram into a Paragraph · 8 minutes
Move from labels to a connected explanation of gas exchange.
Open activity 1 - Retain a Condition in a Summary · 8 minutes
Keep a scientifically important condition when shortening a passage.
Open activity 2 - Repair an Unhelpful Peer Comment · 8 minutes
Turn vague feedback into a usable revision request.
Open activity 3 - Fade a Gas-Exchange Frame · 8 minutes
Move from a supported explanation to independently chosen wording.
Open activity 4
Finish · 8 minutes: remove the models and use the final activity’s fresh-example check.
Plan the lesson for your class
Exit task
Use a different subject mechanism and check the relationship without giving a sentence opening.
Keep the response and record which support was still needed. Plan retrieval in the next lesson using another context.
Questions that keep learners thinking
Which arrow supports each verb in your explanation?
Which small phrase prevents this from becoming an always claim?
Where should the writer act, and what should become clearer?
Which relationship must survive when the frame disappears?
Ask learners to explain a revision or decision rather than simply repeat a teacher model.
Use the sequence flexibly
Choose two routines for a shorter lesson. For learners needing more language support, build in oral rehearsal and reduce the amount written; retain the subject reasoning. For greater independence, provide the task and criteria without the model.
This is an original classroom lesson, not a Cambridge examination task or an endorsed course sequence.