Environmental Design & Evidence-Based Capstone · Grade 12 Science
Chapter: Conservation, Systems & Environmental DesignEnvironmental Design & Evidence-Based Capstone
Learning goals
- I can compare a baseline and alternatives using explicit criteria and calculations.
- I can plan sensitivity analysis and monitoring that addresses confounding variables.
Readings for this unit
Before this unit
Energy accounting, systems, environmental evidence, and algebra.
Use the detailed parent plan: two core 50–60-minute sessions per focused unit, with a third assigned for selected calculation/modeling topics. First study the core explanation and Parts 1–2 with their figures/checks; next study Parts 3–4, the whole-unit application, worked cases, varied practice and exit check. Attempt reasoning before opening guidance. Extend time when actual understanding requires it; investigations and chapter assessments have separate sessions.
Start with something to explain
How can a family judge whether a proposed environmental design really works?
Illustrative evidence case. A clear service target is compared with reproducible prediction and a monitored pilot.
Notice and wonder
Record two observations using the stated quantities or relationships. Keep observations separate from possible causes. Write one question that a new measurement could help answer.
How can a family judge whether a proposed environmental design really works?
Your first model
Start with the baseline, criteria, constraints and alternative designs.
Build the language from the idea
- baseline
- The defined starting condition for comparison.
- sensitivity analysis
- Recalculation using plausible changes in uncertain inputs.
- simple payback
- Upfront cost divided by annual savings in a simplified model.
A capstone brings evidence from physics and environmental science into a feasible design. Begin with a precise problem such as reducing school building energy use while preserving acceptable lighting and temperature. Define the baseline, required service, constraints, and a measurable success criterion.
Collect or use supplied data on energy, costs, and impacts with units and dates. Separate measurements from assumed factors. A design may include insulation, lighting, scheduling, or a renewable supply; each option should connect a mechanism to an expected measurable outcome.
Calculate annual useful service, electricity use, resource demand, and cost using consistent boundaries. A simple payback estimate is upfront cost divided by annual savings; it ignores discounting, maintenance changes, and uncertain future prices. State those limits rather than presenting it as a complete financial decision.
Compare at least two plausible alternatives plus the baseline. Consider life-cycle impacts, reliability, habitat and water effects, safety, and distribution of benefits. Show a sensitivity case for a key uncertain factor, such as use hours or equipment lifetime, to test whether the ranking is robust.
A test plan identifies a prediction, measurement method, comparison condition, repeats, and a threshold for revision. Post-installation monitoring should compare equivalent seasons or weather-adjusted periods. An observed decline after a change can still be influenced by weather, occupancy, or measurement drift.
Present a report with problem, diagrams, assumptions, calculations, evidence, trade-offs, chosen option, and monitoring. The aim is a defensible decision whose reasoning another person can follow, not a polished claim unsupported by data. Parents can assess reasoning with the guide’s criteria without special equipment.
Build your understanding
Use the detailed parent plan: two core 50–60-minute sessions per focused unit, with a third assigned for selected calculation/modeling topics. First study the core explanation and Parts 1–2 with their figures/checks; next study Parts 3–4, the whole-unit application, worked cases, varied practice and exit check. Attempt reasoning before opening guidance. Extend time when actual understanding requires it; investigations and chapter assessments have separate sessions.
Part 1 · Frame a design problem before choosing a solution
A design brief defines a problem, beneficiaries, criteria and constraints before selecting a favored solution. State the service and baseline so improvement can be measured. A vague goal such as “help the environment” needs a specific boundary and outcome, while a narrow energy target should not hide unacceptable service or access losses. Keep stakeholder needs visible and distinguish must-meet constraints from criteria that can be traded against one another.
Read the visual model
Identify the labeled structures and units, then trace the arrows or compare values under the caption’s stated conditions. Separate the displayed evidence from a further inference. Write your reasoning before opening the guidance.
Why is “install a panel” a weaker problem statement than “deliver a defined service within constraints”?
Visual reasoning — after your attempt
It selects a solution before comparing alternatives or defining whether it meets the actual need.
A capstone begins with a defined service, baseline, affected users, measurable criteria, and constraints. Identify the underlying mechanism rather than beginning with a favored technology. Different proposed solutions must meet the same core task to support a meaningful comparison.
For runoff management, specify area, storm conditions, acceptable retained volume, maintenance, and downstream effects before choosing materials.
Pause and explain
Why is naming a technology not a complete problem statement?
Check your reasoning after answering
It does not specify the required service, baseline, constraints, or evidence needed to decide whether the design succeeds.
Part 2 · Combine models with transparent evidence
A capstone model should identify measured inputs, supplied data, estimated factors and assumptions. Show unit conversions and intermediate steps so another reader can reproduce the result. A prediction is not an observation of the proposed design’s future performance. Compare it with a baseline or pilot and explain which discrepancies could arise from measurement, behavior or model limits. Proper source attribution lets families verify external evidence without making those links the only required teaching reference.
Read the visual model
Identify the labeled structures and units, then trace the arrows or compare values under the caption’s stated conditions. Separate the displayed evidence from a further inference. Write your reasoning before opening the guidance.
What should a report say when household data were not actually collected?
Visual reasoning — after your attempt
Identify the supplied or hypothetical dataset honestly and avoid claiming a performed measurement.
Use relevant physics, ecological, and resource models to generate predictions. Label supplied, measured, estimated, and assumed values separately. Cite actual data sources when used, and keep invented practice data clearly illustrative. A precise calculation is not more reliable than its least-supported inputs.
A storage estimate may use area and rainfall, while infiltration needs soil and timing evidence. Do not substitute one model for every process.
Pause and explain
What should a reader be able to reproduce?
Check your reasoning after answering
The input origins, units, assumptions, calculations, and criteria should be explicit enough to reconstruct and challenge the conclusion.
Part 3 · Test alternatives and uncertainty before selecting
An alternatives analysis compares multiple feasible designs under the same service definition. Here B uses 30 fewer energy units per year but has 40 additional up-front units, giving an energy break-even around 1.33 years if conditions persist. Lifespan, maintenance and service quality can change that conclusion. Examine a plausible range and identify what would reverse the ranking; report non-energy criteria alongside the selected account rather than hiding them inside one unsupported score.
Read the visual model
Identify the labeled structures and units, then trace the arrows or compare values under the caption’s stated conditions. Separate the displayed evidence from a further inference. Write your reasoning before opening the guidance.
What if B lasts only one year before replacement?
Visual reasoning — after your attempt
Its 40-unit extra up-front burden exceeds its 30-unit one-year saving, before replacement impacts and other criteria are considered.
Compare at least two feasible options using the same service and boundary. Check constraints before weighted preferences, and vary uncertain inputs to assess sensitivity. If a ranking changes, report the conditions that determine the decision instead of hiding the reversal.
A low-cost option can fail a required capacity; another can meet capacity but require maintenance that must be included in the plan.
Pause and explain
Why is a sensitivity result useful rather than a weakness to conceal?
Check your reasoning after answering
It reveals which assumptions matter and where a targeted measurement can improve the decision.
Part 4 · Present a pilot, revision, and monitoring plan
A pilot tests a manageable version of the design with a baseline, monitoring plan and success criteria. Keep raw records and compare actual service and resource use with predictions. A useful revision explains why a model or choice changed, including unexpected effects and unresolved uncertainty. The final communication should let another family understand the mechanism, reproduce calculations and judge limits without copying an attractive conclusion. A proposal-only project must be labeled as such.
Read the visual model
Identify the labeled structures and units, then trace the arrows or compare values under the caption’s stated conditions. Separate the displayed evidence from a further inference. Write your reasoning before opening the guidance.
What makes a revision substantive rather than cosmetic?
Visual reasoning — after your attempt
It changes or qualifies the model/design because of specific evidence, a discovered assumption or a tested constraint, with reasoning shown.
A finished proposal should include predictions, a test method, uncertainties, maintenance responsibilities, and success measures. Compare pilot outcomes with predictions and revise transparently. Independent written argument and notebook evidence matter more than a polished poster or one automatically scored answer.
A failed trial can improve a design if its measured cause is examined. Keep dated records of changes and explain what each revision tests.
Pause and explain
What makes a capstone conclusion scientifically defensible?
Check your reasoning after answering
It links a feasible design to reproducible evidence, explicit assumptions, measured criteria, and a plan to test unresolved uncertainties.
Apply the whole unit · Choose and test a runoff-storage design
Illustrative 100 m² paved site receives a 20 mm storm. Model A retains 1000 L; model B retains 1500 L. Required retention is at least 60% of predicted runoff. Initially assume all rain becomes runoff; then test a 25 mm storm.
Your task
Calculate runoff and retention fractions, identify which option meets the constraint in each scenario, and propose a pilot and wider-impact account before recommending construction.
What your response should show
- Define the system, quantities, units, and relevant conditions before selecting a model.
- Show intermediate calculations or a labeled evidence account, including signs or denominators.
- Explain how the supplied evidence supports the conclusion rather than reporting only an answer.
- Identify a meaningful uncertainty, model limit, or measurement needed to test the conclusion.
Response guidance — after your attempt
At 20 mm: volume=100×0.020=2.00 m³=2000 L; A retains 50%, B 75%.
Only B meets 60% at 20 mm. At 25 mm, volume=2500 L; A 40%, B 60%.
B meets the modeled threshold in both cases, with no margin at 25 mm; greater runoff or reduced usable capacity could change feasibility.
The result is conditional on rainfall conversion, available storage, and the absence of other losses or flows. A pilot should measure actual runoff timing, usable capacity, outlet behavior, maintenance, and downstream effects. The arithmetic supports choosing B for further testing under the stated constraint, not immediate approval of a real installation.
Scientific references and source-model foundations
Parent / teacher teaching notes
Use the capstone as a defended report with a diagram, calculations, sensitivity, alternatives, and a monitoring plan. Ask the learner what evidence would make them revise the preferred option. Ask the learner to explain each symbol, axis, unit and arrow before calculating. Calculated examples, supplied illustrative records and actual historical observations are labeled separately. Selected public OpenSciEd middle-school source figures are foundation examples, not complete high-school editions or an endorsement; all advanced explanations are supplied locally.
The key idea
A strong design connects mechanism, numbers, trade-offs, uncertainty, and a testable monitoring plan.
Worked examples
Example 1
- Divide upfront cost by annual savings.
- 600/150.
Example 2 · Worked application
- Removal percentage does not identify final concentration or all relevant contaminants.
- One trial lacks reproducibility and a reliable comparison.
- Safety requires applicable criteria and valid testing, not the invention's label.
Use provided datasets for analysis; do not consume experimental treated water.
Example 3
- 10W=.010 kW.
- .010×2000.
Example 4 · Find and fix the mistake
- Test the claim against the stated conditions: Use provided datasets for analysis; do not consume experimental treated water.
- Scale, durability, maintenance, conditions and repeated independent tests still matter.
Use provided datasets for analysis; do not consume experimental treated water.
Example 5 · Reason from the visual model
- An alternatives analysis compares multiple feasible designs under the same service definition. Here B uses 30 fewer energy units per year but has 40 additional up-front units, giving an energy break-even around 1.33 years if conditions persist. Lifespan, maintenance and service quality can change that conclusion. Examine a plausible range and identify what would reverse the ranking; report non-energy criteria alongside the selected account rather than hiding them inside one unsupported score.
- Its 40-unit extra up-front burden exceeds its 30-unit one-year saving, before replacement impacts and other criteria are considered.
Hypothetical energy-only comparison with equal service assumed; not real product data.
Avoid these mistakes
- Simple payback is a limited model, not a complete cost analysis.
Check your understanding
How would you respond if post-change data failed your prediction?
Discuss the answer
Inspect measurements and confounders, compare actual conditions with assumptions, revise the model or design, and document the evidence.
Return to the phenomenon
Return to the initial case. How can a family judge whether a proposed environmental design really works? Revise your drawing or explanation using two named ideas and one stated limitation.
Compare explanations after your attempt
Connect measurements to a model, test assumptions and compare actual outcomes; communicate evidence-supported revisions and remaining limits.
What should we investigate next?
Which comparison would test a remaining uncertainty? State what you would change, keep comparable and measure.
Investigate, calculate and revise
Keep a first model and an evidence-supported revision. Attempt each task before opening guidance; all required explanations and supplied-data routes are available locally.
Activity 1 · Return to the opening case
Use the opening phenomenon, unit definitions and explained Parts 1–4.
Your task
Return to the initial case. How can a family judge whether a proposed environmental design really works? Revise your drawing or explanation using two named ideas and one stated limitation.
Success criteria
- Use the stated observations and appropriate units.
- Connect a labeled model with the physical/environmental mechanism.
- State assumptions and an evidence limitation.
- Explain a substantive revision or next test.
Hint
Keep object/material identity, material transfer and energy account distinct.
Response guidance — discuss after your attempt
Connect measurements to a model, test assumptions and compare actual outcomes; communicate evidence-supported revisions and remaining limits.
Activity 2 · Transfer to a changed case
Cover the worked answer and use the explained models, relationships and notebook.
Your task
A proposed change saves 12 W for 1500 h/year while providing the same service. Its extra production energy is 24 kWh. Find annual saving and energy break-even; name one pilot measure beyond energy.
Success criteria
- Use the stated measurements or conditions, with correct units.
- Connect the result to the physical or environmental mechanism or evidence relationship.
- Identify the assumption, model limit or further evidence requested.
Hint
Name known quantities and conditions, show intermediate steps and check conservation.
Response guidance — discuss after your attempt
Annual saving=0.012×1500=18 kWh. Energy break-even=24/18≈1.33 years under fixed use/lifespan assumptions. Measure service adequacy, reliability, actual hours, access or maintenance as a separate pilot outcome.
Words to know
- baseline
- The defined starting condition for comparison.
- sensitivity analysis
- Recalculation using plausible changes in uncertain inputs.
- simple payback
- Upfront cost divided by annual savings in a simplified model.
In the real world
Use the chapter investigation to connect this unit to measured evidence and a practical decision.
Exit check
How would you respond if post-change data failed your prediction?
Check your explanation after answering
Inspect measurements and confounders, compare actual conditions with assumptions, revise the model or design, and document the evidence.
Explain your reasoning without notes. If a key idea is missing, revisit the lesson and try again.