Year 5 · 65 minutes · Objectives
What happens when we reward the easy thing to count?
A proxy is a measurable substitute for something we care about. Click count may be used as a proxy for useful reading, but quick sensational snippets can earn many clicks with little reading value. This allocation model computes two different outcomes from supplied fictional coefficients. Neither coefficient is a universal measure of learning. Choosing and questioning the objective is a human responsibility.
Set the fictional library purpose: help readers spend time with useful material. Print three resource types with click and reading-value coefficients. Clarify that the values are deliberately simplified and not ratings of real genres.
Distinguish a measured score from the purpose it represents. Useful earlier investigations: y4-threshold Use pairs with predictor/operator roles. Swap after the first comparison. Each learner draws or writes their own explanation using one exact case.
Australian Curriculum Version 9 · Digital Technologies: AC9TDI6P01, AC9TDI6P06. Selected aspects only. This activity contributes evidence; it does not cover the full descriptor or achievement standard. A programming descriptor is not claimed for merely moving controls. ACARA AI curriculum connection · V9 Technologies These are planning connections, not ACARA endorsement or exhaustive descriptor alignment.
Compare a useful reading experience with a quick click.
Ask: “Can you click without learning much?”
Listen for: “Yes, the headline might be enough to attract a click.”
Predict which resource a click-maximiser will favour before allocating the budget.
Ask: “What would a system pursuing only this number choose?”
Listen for: “The item with the largest click coefficient.”
Move tokens between resource types; inspect both computed clicks and reading value. Keep the total budget fixed.
Ask: “Which change raised the scoreboard but hurt the purpose measure?”
Listen for: “Moving tokens toward high-click, low-reading snippets.”
Find an extreme allocation that wins on clicks and loses on reading value.
Ask: “Did the optimiser fail to follow its goal?”
Listen for: “No, the goal was poorly chosen.”
Create a weighted objective or a minimum reading-value constraint. Test the same allocations and identify a new way it might be gamed.
Ask: “Does a combined score remove the need for judgement?”
Listen for: “No, we chose its weights and it still misses things.”
Submit a purpose/proxy table and two compared allocations.
Ask: “What should a human review that the score cannot see?”
Listen for: “Whether the resources actually help the intended readers.”
A measurable score is the real goal.
With a fixed token budget, predict which allocation maximises clicks and what happens to reading value.
The highest-click allocation can have the lowest supplied reading-value total.
Add a reading constraint or new weighting and test the same allocations; disclose the fictional coefficients and omitted outcomes.
Check learners explain that successful optimisation can implement the wrong objective. Ask for a concrete allocation proving the divergence.
Use five tokens and whole-number coefficients. Compare only two resource types initially.
Find allocations that cannot improve one measure without worsening the other and sketch a Pareto frontier.
A revised library objective with a counterexample and a tested allocation.
All resource types and coefficients are invented. Do not use the score to rank classmates, teachers or reading ability.
Enumerate large allocation spaces, calculate multi-objective frontiers on GPU and compare how different weights hide or expose trade-offs.
| Criterion | Beginning | Secure | Extending |
|---|---|---|---|
| Proxy diagnosis | Equates clicks with benefit | Shows a numerical divergence | Explains why optimisation amplifies it |
| Objective redesign | Replaces one unexplained score | Justifies a constraint or weighting | Tests it and identifies a remaining gaming strategy |
Australian Curriculum Version 9 · Digital Technologies
References: AC9TDI6P01, AC9TDI6P06. Read the current source (checked 2026-09-07).
Evidence to assess: A revised library objective with a counterexample and a tested allocation.
Selected aspects only. This activity contributes evidence; it does not cover the full descriptor or achievement standard. A programming descriptor is not claimed for merely moving controls. Moderate the supplied illustrative responses against your school unit and current achievement standard.
These are planning estimates to test with your class. A short session develops one supported claim; it does not compress the whole senior project.
| Stage | 45 minute focus | 60 minute investigation |
|---|---|---|
| Readiness and prediction | 0–5 | 0–5 |
| Trace the supplied example | 5–13 | 5–15 |
| Author and run cases | 13–25 | 15–35 |
| Counterexample and redesign | 25–35 | 35–45 |
| Explain and discuss | 35–42 | 45–55 |
| Export and handover | 42–45 | 55–60 |
For a longer project, use three 50-minute sessions. Session 1 (0–50): readiness, model, hypothesis and initial cases. Export a project and record the next test. Session 2 (50–100): reopen, check settings, author counterexamples and revise the design. Export the changed project and identify unresolved evidence. Session 3 (100–150): independent peer test, final artefact, individual explanation and moderation. If using two 60-minute sessions, stop at minute 60 after saving the first comparison; use 60–120 for redesign, independent test and defence.
Entry check: Distinguish a measured score from the purpose it represents. Ask the learner to demonstrate it before choosing the level of support.
Preparation: allow about 15 minutes to run the starter, print the cards and check a project can be reopened. This estimate has not yet been measured in a classroom pilot.
Read the entry question aloud, model one row, and label the units. Offer the case table as a large-print sheet. Keep mathematical derivations optional until the learner can explain the comparison.
For one device, use a projector: one pair predicts, one operates, and the class records on paper. Swap roles after the first comparison. For individual access, support keyboard controls and a written table equivalent to each visual. Learners may explain orally or with an annotated diagram. Never require personal data, a recorded voice, or a photograph.
Mixed readiness: if the entry check is difficult, use the linked prerequisite and the first two case cards; retain the same central question. If secure, ask the learner to design an unseen test and state which explanation it could disprove.
Score each case as weighted pages plus weighted questions correct. Compare rankings as the rule changes.
Starting parameters: Pages weight = 1, Understanding weight = 0
3 cases calculated from your supplied inputs. Compare the evidence with your prediction.
| reader | pages | minutes | understanding | score |
|---|---|---|---|---|
| Bo | 30 | 20 | 2 | 30 |
| Kiki | 20 | 15 | 3 | 20 |
| Pip | 12 | 25 | 5 | 12 |
These are authored examples, not work collected from children. Assess reasoning using the lesson rubric, not whether the first prediction was correct.
Beginning: “It worked because the result looks right.” This identifies no exact case, control or measurement. Ask the learner to point to one row and say what happened.
Developing: “In the first case I recorded reader: Bo; pages: 30; minutes: 20; understanding: 2; score: 30.” This cites evidence, but does not yet explain how the result follows from the rule. Ask the learner to trace the relevant step.
Secure: “For the first supplied case, reader: Bo; pages: 30; minutes: 20; understanding: 2; score: 30. I can trace it using this mechanism: Score each case as weighted pages plus weighted questions correct. Compare rankings as the rule changes. My result supports a claim about these supplied cases. It does not establish that the same result holds outside them.” Look for an accurate trace, the actual settings and a bounded claim; accept equivalent oral or visual evidence.
Extending: The learner constructs and reruns a new case, reports whether the first explanation survives, and defends a revised design. Use this concrete challenge: Design two scoring rules for a fictional reading club. Include one important outcome the score can miss. Require the original and changed evidence and this boundary: Neither supplied measure captures enjoyment, access or every aspect of understanding.
Moderation: first assess independently against each lesson criterion. Compare the exact trace or artefact that led to your judgement. Resolve differences using evidence, not polished language. Keep each learner's individual explanation even when the artefact was produced in a group.