# Science · Year 9 · optional Days 11–20

Ten separate **12-minute additions** sample carbon transfer, scientific method, waves and atom conservation. This is not a complete Science sequence. All counters/readings are fictional or representational, never measurements of air, health or safety. Use the [clean learner copy](LEARNER-COPY.md), [inquiry mat](print/science-inquiry.pdf), [source ledger](SOURCE-AND-RIGHTS.md) and [teacher key](teacher/ANSWER-AND-NEXT.md). No chemicals, flames, sensors or electric devices are required. For each block, the teacher records a source detail, reasoning and any access/content prompt separately.

### Day 11 · Where a carbon arrow starts and ends · AC9S9U03, AC9S9I04
**Kit:** paper labels `atmosphere / plant / soil`; original arrow `atmospheric CO₂ → plant carbon` labelled *photosynthesis*. 0–2: State that the diagram is a simplified process model, not a local carbon measurement. 2–4: Predict which direction the labelled photosynthesis arrow points. 4–10: Place arrow, name atmosphere and biosphere, then add a possible return arrow labelled *respiration* without assuming equal amounts. 10–12: Check: photosynthesis takes carbon from atmospheric CO₂ into plant material; the card says nothing about a rate. **Routes:** move printed labels; build a raised-token sequence; dictate a precise text diagram. **Response move:** if arrows are treated as identical amounts, ask for a measured flux before comparing size. **Home:** describe one omitted reservoir, with no field collection.

### Day 12 · Processes are not interchangeable · AC9S9U03, AC9S9I06
**Kit:** three original cards `plant takes in CO₂ in photosynthesis`, `living organisms release CO₂ in respiration`, `fuel combustion releases CO₂`, after the [NASA carbon-cycle explanation](SOURCE-AND-RIGHTS.md). 0–2: Label each as a general process, not a claim about a named town. 2–4: Predict the arrow direction relative to the atmosphere. 4–10: Sort the three cards, then critique “every upward arrow is respiration”; name combustion as another pathway and one omitted condition. 10–12: Check: one arrow symbol cannot tell us its process without a label. **Routes:** orient arrow strips; read a linear text chain; compare aloud/AAC. **Response move:** if combustion is called photosynthesis, trace where atmospheric CO₂ enters/leaves in each description. **Home:** add a question a full carbon model must answer; no personal emissions diary.

### Day 13 · Design a fair model comparison · AC9S9I01, AC9S9I02
**Kit:** paper-only scenario: two groups intend to compare how far an identical paper disc travels from a ramp raised by one or two support blocks; no real test is run. 0–2: Define a *model-planning question*, not a conducted investigation. 2–4: Predict a direction cautiously and identify ramp height as the changed factor. 4–10: Plan the same disc, ramp surface and release point; say what must be recorded over repeated trials and how travel distance would be measured. 10–12: Check: varying both release point and ramp height prevents a clean comparison. **Routes:** place variable/control cards; complete a structured text plan; challenge a flawed plan orally. **Response move:** if a prediction is presented as a result, ask where the observations are. **Home:** rewrite the question for another harmless paper model.

### Day 14 · Keep an anomaly visible · AC9S9I05, AC9S9I06
**Kit:** fictional counter readings `12, 13, 12, 20` arbitrary units from four cards; note says *card 4 was read after its boundary label moved*. These are **not carbon data**. 0–2: Name the invented status and unit. 2–4: Predict which reading merits a method check. 4–10: Mark all four on a number line, describe the cluster 12–13 and anomalous 20, then propose re-reading with the boundary held still. 10–12: Check: the moved label is a possible explanation, not proof that 20 is wrong. **Routes:** number tiles; tactile raised marks; spoken table audit. **Response move:** do not silently delete 20 or average away the method note. **Home:** state one reason repeated observations matter.

### Day 15 · Fresh Science check A · AC9S9U03, AC9S9I06
**Kit:** new carbon-arrow/model-limits case [S-A](ASSESSMENT.md), publicly accessible alongside its teacher key. 0–2: Revisit source versus model words only. 2–4: Offer neutral text access without previewing the case in class. 4–10: Collect a first response to S-A; use a locally unseen equivalent if prior access matters. 10–12: Record the arrow explanation and stated limit separately before consulting the [teacher key](teacher/ANSWER-AND-NEXT.md). **Routes:** labelled cards; linear text; learner-dictated explanation. **Response move:** reteach the specific arrow or claim boundary with a *different* diagram after collection. **Home:** choose a new model and name one feature it omits.

### Day 16 · A sound wave needs a medium · AC9S9U04
**Kit:** original text cards `tap in air / sound from a speaker in air / same source imagined in a vacuum`; no speaker or loud demonstration. 0–2: Say these are scenarios, not measurements. 2–4: Predict whether a mechanical sound wave can cross an empty vacuum. 4–10: Draw or direct a sequence of neighbouring air-particle motions for the air case; explain why this model stops without a medium and what the dots do **not** show (actual molecule paths or loudness). 10–12: Check: sound does not carry through a vacuum; light behaves differently. **Routes:** paper dot row; tactile dots; spoken/AAC particle-model critique. **Response move:** if particles are drawn travelling with the sound across the room, show a local back-and-forth motion. **Home:** describe the model without making or recording noise.

### Day 17 · Choose a wave model for a question · AC9S9U04, AC9S9I04
**Kit:** original `crest–trough–crest` paper strip and `dot-neighbour-dot` strip. 0–2: Name both as simplified representations. 2–4: Ask which better shows a repeating spatial pattern and which suggests neighbouring medium particles. 4–10: Choose one for the fictional question “How might a disturbance move through air?”, state one strength and one omission; do **not** infer sound speed from spacing. 10–12: Check: the picture can represent transfer without moving a whole row of air from source to ear. **Routes:** compare raised strips; write two sentences; direct a partner's card placement. **Response move:** match the chosen representation to the actual question. **Home:** sketch one changed feature and what it would mean.

### Day 18 · Count atoms, not pictures · AC9S9U07
**Kit:** original H and O letter counters beside `2H₂ + O₂ → 2H₂O`; symbols represent the balanced hydrogen–oxygen reaction in [RSC guidance](SOURCE-AND-RIGHTS.md), not a classroom experiment. 0–2: Identify subscripts and coefficients. 2–4: Predict H and O counts on each side. 4–10: Count left H=4/O=2 and right H=4/O=2; explain why changing H₂O to H₂O₂ is not a permissible balancing step. 10–12: Check: a coefficient changes the number of whole formula units; a subscript changes the substance representation. **Routes:** four H/two O counters; text count table; oral equation audit. **Response move:** if a learner changes subscripts, rebuild with whole molecule cards. **Home:** practise counting a *supplied* paper equation; do not mix substances.

### Day 19 · Review a claim before repeating it · AC9S9H01, AC9S9I07
**Kit:** invented note: “A single paper model worked once; therefore the finding is reliable for all classrooms.” No method, repetitions, reviewer or classroom outcome is given. 0–2: Label it a fictional claim. 2–4: Predict two questions another reviewer should ask. 4–10: Write a three-line peer-review memo: source/method needed, one narrower statement, one reproducible next test. Explain that feedback and publication can refine science without guaranteeing a claim is true. 10–12: Check: one successful demonstration is not universal evidence. **Routes:** review-card sort; audio/AAC memo; marked-up draft. **Response move:** if “peer reviewed” is used as proof, ask what independent method/detail was actually examined. **Home:** phrase a fair critique of an invented claim.

### Day 20 · Fresh Science check B · AC9S9U04, AC9S9U07, AC9S9I06
**Kit:** new wave-model and atom-count case [S-B](ASSESSMENT.md), also publicly accessible. 0–2: Recall how to label a model and count each element. 2–4: Give response/access instructions only. 4–10: Collect a first response to S-B; substitute a locally unseen equivalent if needed. 10–12: Collect before coaching; key separates wave-medium reasoning, atom conservation and model limits. **Routes:** tactile tokens; text table; spoken/AAC explanation. **Response move:** use a new equation or medium scenario after collection to target the missing idea. **Home:** describe one scientific model's useful and omitted feature.

All new prose/cards © NeuroForgeIO Pty Ltd 2026, [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/). External science principles are attributed in the source ledger.