The 320-word spread on the water cycle
A Grade 6 CLIL science teacher is planning a unit on the water cycle for 26 learners at CEFR B1. The class textbook - written for L1 learners - has a 320-word spread containing 14 terms the class has not met (precipitation, transpiration, condensation, run-off, aquifer, impermeable…). The prose is heavily nominalised and passive: 'Precipitation occurs when water vapour, having condensed upon contact with cooler air masses, is returned to the surface.' There is one small diagram with unlabelled arrows and a glossary at the back of the book. In a pilot lesson the class needed 20 minutes to read the spread, and in the following discussion learners could name terms but could not sequence the cycle or explain why condensation happens. The teacher's plan is to 'go through the glossary first' and then set comprehension questions 1–8.
1. Explain why the glossary-first plan is unlikely to fix the problem. Refer to lexical density, nominalisation and the nature of the reading task.
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The glossary treats the wrong unit of difficulty.
- Nominalisation is the main barrier, and a glossary entry cannot unpack it. Precipitation is a whole clause compressed into a noun: water falls from clouds to the ground. Giving the translation gives a label, not the process. Learners can then name the term - exactly the outcome observed in the pilot - without being able to sequence or explain anything.
- Lexical density. The sentence quoted packs several content words and a subordinate participle clause into one unit; there are few cohesive links for a B1 reader to hold on to. Fourteen new items in 320 words is far more than can be processed and retained in one lesson; a list does not build the network between them.
- The passive hides the agent. '…is returned to the surface' removes who/what does the returning, and the causal chain - the thing the learners are supposed to learn - disappears.
- Split attention. A glossary at the back of the book forces learners to leave the text on every unknown word, which fragments the reading and explains the 20 minutes.
- Questions 1–8 test the text, not the concept. If they can be answered by locating a sentence, they will reward the glossary work and confirm the illusion of understanding.
A better diagnosis: the material is linguistically too dense for the concept to be visible, which is a materials problem, not a vocabulary-list problem.
2. Propose three adaptations to the material and justify each with a CLIL principle.
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Adaptation 1 - make the diagram the first text, not the illustration. Enlarge it; replace the unlabelled arrows with a blank flow frame the class completes together; add the key terms to the diagram rather than to a list. Principle: dual coding and visual support - the same content is carried in two channels, lowering the linguistic load while keeping the cognitive demand (sequencing a cycle) intact. It also removes the split attention created by the back-of-book glossary.
Adaptation 2 - unpack the nominalisations into verbs, in a process frame. Rewrite the model sentence as a chain the class can manipulate: 'Water ______ from the sea. It ______ into the air. When it cools, it ______ and forms ______.' Keep the technical nouns but attach them to the process. Principle: focus on form / noticing the academic register - learners meet the same concept in accessible syntax first and are then shown the nominalised version, so they learn to unpack it rather than memorise it.
Adaptation 3 - replace questions 1–8 with a sequencing and reasoning task. Cut the diagram into cards (sun, sea, vapour, cloud, rain, river), have groups order them and then answer one 'why' question: 'Why does condensation happen when the air cools?' Principle: task before text and higher-order thinking - the reading becomes a resource for solving a problem rather than a comprehension test, and the reasoning demand is preserved while the language demand is staged.
Supporting move: pre-teach only five or six generative items (condense, evaporate, vapour, flow, cool, absorb) - the ones that unlock the rest - rather than all fourteen.
3. How would you decide whether to simplify the text or keep it and scaffold it? Give criteria.
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Criteria to apply:
- Is the text the content, or a vehicle for the content? Here the objective is the water cycle, not the reading of an academic spread - so simplification is legitimate. If the objective were 'read an academic explanation', the text would have to be preserved and scaffolded.
- Will this register be assessed? If the learners will meet nominalised, passive science prose in an examination, they need planned exposure to it - but exposure with support, not exposure instead of support.
- The size of the proficiency gap. At B1 with 14 unknown terms, keeping the text unchanged and adding a glossary has already been shown not to work. A gap this size calls for rewriting.
- Time and re-exposure. A defensible compromise: simplify for the first encounter, then bring back one or two authentic sentences later in the unit with the unpacking already modelled.
The guiding rule: simplify the language, not the thinking. It is acceptable to change 'Precipitation occurs when water vapour, having condensed…' into 'Water vapour cools and condenses. It then falls as rain.' It is not acceptable to replace 'explain why condensation happens' with 'name three types of precipitation', because that removes the cognitive demand the unit exists to teach.
A further test: if the adapted material can be completed without understanding the cycle - for example by matching words - it has been oversimplified.