Design justification CER
Do now
Students write a CER justifying their app design choices against user needs and usability principles.
- Hand in
- CER with a specific design-claim, persona and feature-list evidence, reasoning linking choices to usability principles, a communication improvement prediction, and design assumptions and limitations.
- Where
- Turn this in at the drop folder with your district Microsoft sign-in, or hand it to Mr. Mendoza in class. Both count as submitted. Doing the activity in myPLTW does not.
You get two school days for every day you were absent, so this deadline moves with you.
Your team put a big 'Nearest Open Clinic' button on screen one. Prove it: which specific persona need and which usability principle make that the right call, rather than just what looked good?
Students write a CER justifying their app design choices against user needs and usability principles.
- • Write a CER justifying design choices with user-need evidence.
- • Tie choices to usability principles and state one limitation.
- State one feature your team designed and the exact user need it answers.
- Finish this sentence: 'This choice serves the user because...' for that feature.
- 1State a claim that the design meets the target users' surge needs.
- 2Cite persona and feature-list evidence tied to specific needs.
- 3Explain reasoning that links each design choice to a usability principle.
- 4Predict how the design improves communication during a surge.
- 5Identify assumptions and limitations in the design process.
What did this day actually feel like?
Design justification CER and device ethics
ETHICS MONDAY Two things today because of the compression. First the CER justifying our app design against the personas and usability principles, proving each choice serves a real need rather than a preference.
Then the device ethics debate: how much testing should a new biomedical device require before it reaches patients? Speed and safety in direct tension. More testing protects people and delays access for people who are suffering right now. Somebody pointed out that the people harmed by delay are invisible in a way the people harmed by a bad device are not, and that asymmetry is why the debate never resolves cleanly.
AT HOME, THE NIGHT BEFORE THU DEC 10 Engineering design notes The seven stages of the engineering design process, and how CAD turns a concept into something you can test.
The framing that mattered: design is a loop, not a line. Every test produces data that feeds the next version, so a failed prototype is an input rather than an ending.
Kept in the notebook for the testing lab.
Turned in: CER → Claim Evidence Reasoning folder, plus the exit ticket
Fiction. There is no such student. The lessons, labs and dates are the real planned course; the student, the classmates and the conversations are invented.
🛠 Get unstuck · pick your level
🔑 Today's words · 5
Tap a word in the lesson for a plain meaning and one example. Recycled into next week's Do-Now.
Do the work · 80-minute blockfirst 5 min = hook▸
💡 Big idea: A design is defensible only when each feature traces to user evidence, so a CER forces justification because it makes you link every choice to a real need and a usability principle.
- 0-8 minReview Wednesday personas and wireframe; identify two design choices you can most strongly justify.
- 8-20 minWrite the claim: one sentence stating the design meets target users' surge communication needs.
- 20-42 minWrite evidence: cite persona needs and specific feature-list items as separate evidence points.
- 42-58 minWrite reasoning: link each design choice to a named usability principle.
- 58-70 minWrite prediction and add design assumptions and limitations.
- 70-80 min: confirm claim is specific, evidence cites persona, limitation is stated.
- • Your team designed an app yesterday; today you write the individual argument for why each choice was the right one.
- • The CER claim must be specific: not 'the design is good' but 'the design meets the communication needs of elderly users during a surge.'
- • Cite the persona and feature list, not just your memory of the discussion.
- • Your prediction tells the reader what will happen differently because of your design, compared to no app at all.
- • Design justification means tracing each feature back to a specific persona need and a usability principle.
- • A prediction about improved communication is based on mechanism, not hope: link the feature to the behavior change it enables.
- • Design assumptions include: that the persona is realistic, that users have smartphones, and that the surge scenario is accurate.
Unit 3.2 to 3.3: Medical surge, mobile response facility, public-health communication, app design concept. · Design justification CER
Day 4 of this lesson. Open this exact section in myPLTW (find it in Clever, Microsoft sign-in), then do the work below.
Do this: Open myPLTW and find the Lesson 3.3 Information Sharing design justification or CER activity to use as a writing scaffold.
Submit any platform prompts before shifting to independent CER writing.
Platform prompts done in first 10 minutes; full CER submitted before end of period.
Submitted CER on the class site, or hand it to Mr. Mendoza in class is the primary evidence.
The official PLTW activity stays inside myPLTW. If myPLTW will not open, use F1 and E1-E3 on this page to complete today's local evidence decision, then make up the official activity when access returns. Turn this in at the drop folder with your district Microsoft sign-in, or hand it to Mr. Mendoza in class. Both count as submitted. Doing the activity in myPLTW does not.
Check things off as you work, then submit. This tells Mr. Mendoza how you're doing so he can help the class. It does not replace turning in your producible through the submission route shown below.
Use the code Mr. Mendoza gave you, not your name. Saved on this device.
Unit 3.2 to 3.3: Medical surge, mobile response facility, public-health communication, app design concept. · Design justification CER
Open myPLTW and find the Lesson 3.3 Information Sharing design justification or CER activity to use as a writing scaffold.
Platform prompts done in first 10 minutes; full CER submitted before end of period.
This is how Mr. Mendoza sees the class keeping pace with PLTW. Be honest, it only helps if it is accurate.
🎯 Students write a CER justifying their app design choices against user needs and usability principles.
- State a claim that the design meets the target users' surge needs.
- Cite persona and feature-list evidence tied to specific needs.
- Explain reasoning that links each design choice to a usability principle.
- Predict how the design improves communication during a surge.
- Identify assumptions and limitations in the design process.
CER: CER with a specific design-claim, persona and feature-list evidence, reasoning linking choices to usability principles, a communication improvement prediction, and design assumptions and limitations.
Turn this in at the drop folder with your district Microsoft sign-in, or hand it to Mr. Mendoza in class. Both count as submitted. Doing the activity in myPLTW does not. Use the checklist just below and upload by 11:29 PM for full credit. Absent with an excused absence? You get two school days for every day you were absent, so this deadline moves with you.
| Task | Who |
|---|---|
| State a claim that the design meets the target users' surge needs. | _______ |
| Cite persona and feature-list evidence tied to specific needs. | _______ |
| Explain reasoning that links each design choice to a usability principle. | _______ |
| Predict how the design improves communication during a surge. | _______ |
| Identify assumptions and limitations in the design process. | _______ |
Working solo? Put your own name in "Who" for every row.
- Write a CER justifying design choices with user-need evidence.
- Tie choices to usability principles and state one limitation.
- 1Do thisStudents write a CER justifying their app design choices against user needs and usability principles.
- 2Use this resource
- 3Submit thisCER: CER with a specific design-claim, persona and feature-list evidence, reasoning linking choices to usability principles, a communication improvement prediction, and design assumptions and limitations.
- 4Submit it here
- 1Open the drop folder.
- 2Sign in with your district Microsoft account, not a personal one.
- 3Upload the file, named Lastname_Firstname__Assignment Title.
- 4Your own upload panel says Uploaded with a green check: that is your receipt.
Turn this in at the drop folder with your district Microsoft sign-in, or hand it to Mr. Mendoza in class. Both count as submitted. Doing the activity in myPLTW does not. Principles of Biomedical Technology (Principles of Biomedical Science) › Unit 3.2 to 3.3: Medical surge, mobile response facility, public-health communication, app design concept. › CEROpen the drop folder
Learn it · deck, reading, and vocabulary▸
The deck carries the prior idea forward, lets you inspect an analogy, maps the rule to biology, and ends with the same evidence decision and exit ticket used on this page.
Generated from this lesson's canonical data with a red-team citation check.
A design serves people only when it is built around a real persona's needs, so a wireframe that ignores the persona is design fiction because nothing on it is ranked by real urgency.
A design is defensible only when each feature traces to user evidence, so a CER forces justification because it makes you link every choice to a real need and a usability principle.
A bridge prototype is tested against a load limit, cost limit, and user need before revision.
- Which requirement is a criterion?
- Which limit is a constraint?
- What test result should trigger a redesign?
A design improves when evidence is compared with explicit criteria and constraints.
Biomedical designs also require , ethics, and biological validation beyond a physical prototype test.
- • Bridge requirements map to design criteria.
- • Load results map to E1-E3.
- • Revision maps to the next evidence-based iteration.
Driving question: Your team put a big 'Nearest Open Clinic' button on screen one. Prove it: which specific persona need and which usability principle make that the right call, rather than just what looked good?
What you already know: A design serves people only when it is built around a real persona's needs, so a wireframe that ignores the persona is design fiction because nothing on it is ranked by real urgency.
New idea: A design is defensible only when each feature traces to user evidence, so a CER forces justification because it makes you link every choice to a real need and a usability principle.
Visual or model: F1. F1. A lesson illustration or teaching diagram for Design justification CER. Use it with E1-E3; it is a model or context image, not experimental or patient data. What to notice: Trace the labeled observation or evidence sequence before choosing an explanation.
- Observe or measure the relevant feature in Design justification CER.
- Organize the observation with a stable evidence ID.
- Apply this rule: A design improves when evidence is compared with explicit criteria and constraints.
- Choose the option the evidence supports and state the limit of the conclusion.
Real biomedical example: Your team put a big 'Nearest Open Clinic' button on screen one. Prove it: which specific persona need and which usability principle make that the right call, rather than just what looked good?
What the evidence supports: E1-E3 and F1 support the daily take-home when the response meets the stated success criteria.
What it cannot prove: The package does not support claims beyond this lesson's or any real patient diagnosis.
- • : A health system's ability to rapidly expand staff, beds, and supplies to handle a sudden jump in patients during an emergency or outbreak.
- • : Healthcare delivered to people where they are, using vehicles or portable units to reach communities far from a fixed clinic or hospital.
- • : The science of protecting and improving the health of whole communities through prevention, education, and policies rather than treating one patient at a time.
- • surveillance: The ongoing, systematic collection and analysis of health data to detect disease early, track its trends, and trigger a timely response.
- • communication: Sharing information clearly and accurately between people, which in healthcare keeps patients safe and helps teams coordinate care.
- • usability: How easy, efficient, and satisfying a product is for its intended users to learn and use to reach their goals.
Use it now: Choose one decision option. Cite E1 and E3, then explain how the rule connects the evidence to your choice.
Go further, optional: The source links below are optional enrichment. Every fact required for today's local evidence decision appears in this lesson package.
Design justification means tracing each feature back to a specific persona need and a usability principle.
Limit: E1 supplies context or an observation; it does not by itself establish the explanation.
A design is defensible only when each feature traces to user evidence, so a CER forces justification because it makes you link every choice to a real need and a usability principle.
Limit: E2 is a teaching statement or comparison and must be checked against the task evidence.
Write a CER justifying design choices with user-need evidence.
Limit: E3 supports only the result or product criterion named here; it cannot justify a broader clinical or causal claim.
PLTW-PBT-2026-12-07 · Simulated classroom evidence scenario
Your role: biomedical investigator
Decision: Your team must decide what the evidence from Design justification CER supports before submitting the claim-evidence-reasoning response named on the lesson page.
- • Keep the current design.
- • Revise the feature that misses a criterion.
- • Run one more fair test before choosing.
Response: State one choice, cite at least two evidence IDs, explain the rule that connects them, and add one limitation. Submit it as the claim-evidence-reasoning response.
Claim ceiling: The supplied lesson evidence can support an observation, pattern, classroom mechanism, or next-step decision about Design justification CER. It cannot by itself prove causation, establish a real clinical diagnosis, or justify action outside this classroom task.
- • The solution must address the stated need in Design justification CER.
- • The decision must be supported by E1-E3.
- • The final product must make the success criteria visible.
- • Complete the work inside the 80-minute block.
- • Use only supplied or teacher-approved materials and evidence.
- • Do not trade , accessibility, or privacy for speed.
- • and evidence quality: must pass before scoring other criteria.
- • User need and effectiveness: highest scored criterion.
- • Time, cost, and ease of use: compare only after and effectiveness pass.
Test evidence: For each option, record the E1-E3 result that supports or fails each criterion. Do not assign a score without a named observation.
- Version or option tested
- Criterion met or missed
- Evidence ID and result
- Revision made
- Reason for the revision
- Need and user
- Criteria and constraints
- Chosen option and evidence
- Test result
- Revision and reason
Students often think Students believe explaining a design means describing what the feature does or saying it looks good and feels intuitive.. The trap: That is a trap, because describing a feature is not justifying it. A real justification traces the choice to a specific persona need and a named usability principle, so 'it looks clean' is opinion while 'it serves a rushed parent's need for speed, meeting the efficiency principle' is evidence.
Claim: Our lobby wayfinding kiosk design meets the navigation needs of our two target users at a large hospital, an older first-time visitor named Ellen and a hurried delivery driver named Marcus.\n\nEvidence (persona and feature list): Ellen needs to reach a department she has never visited and reads slowly, so we made the home screen a single large question, "Where are you going?", with a short list of the most-visited departments in big high-contrast text. Marcus needs the loading dock and its entrance quickly and only glances at the screen, so we added a persistent "Deliveries and Dock" button in the same fixed spot on every screen and a printable step-by-step route card.\n\nReasoning (tie each choice to a usability principle): The single-question home screen serves simplicity, because it removes competing choices and shows one clear task at a time. The big high-contrast text serves accessibility, so a user with weaker vision like Ellen can still read it without help. The fixed-position "Deliveries and Dock" button serves consistency, because Marcus can find the same control in the same place every time and does not have to relearn the screen. The printable route card serves memory support, so a user does not have to hold every turn in their head while walking a long hallway.\n\nPrediction: Because the design cuts the reading load and the number of choices that usually make people freeze or ask staff for help, more visitors should reach the right department on their own and fewer should crowd the information desk, which is the behavior change we want in a busy lobby.\n\nAssumptions and limitations: We assume our two personas represent most kiosk users, that visitors can stand and touch a screen, and that department names on the kiosk match the signs in the hallways. If many users are in wheelchairs and cannot reach a tall screen, or if the building signs use different names than the kiosk, then the design would fail those users and our claim would need to change. A lower screen height and matching signage would matter more than any button we added.
This model shows the level of evidence and organization needed to complete: Parallel worked model of a design-justification CER: for a different product (a hospital lobby wayfinding kiosk), it traces each design choice to a persona need and a usability principle, predicts the effect on behavior, and states assumptions and limitations, so students see the format and depth without seeing an answer to their own clinic-app prompt.
- Write one defensible claim.
- Choose specific evidence that supports the claim.
- Explain the scientific rule that connects the evidence to the claim.
Keep the structure. Replace the question, facts, measurements, and evidence. Then recheck units, vocabulary, and whether the conclusion goes beyond the evidence.
Also due today: Submit your CER on the class site, or hand it to Mr. Mendoza in class before end of period.
- CER:
- Claim, Evidence, Reasoning: make a claim, back it with evidence, explain your reasoning.
- SOP:
- Standard Operating Procedure, the exact steps to follow (especially in a lab).
- Tracker:
- Your PLTW progress log where you record completed evidence.
- myPLTW:
- The PLTW course site where you do the online activities. Find it in Clever with your Microsoft sign-in, right next to Schoology.
Tap the speaker to hear a term. Add two of these to your notebook glossary with a definition and an example in your own words.
Pick just 2 or 3 words from today and make them yours: write what each one means in your own words, name the context clue or evidence that helped, then give one example from what you actually did in Design justification CER. Try your own words first; the glossary is there if you get stuck. This is voluntary and counts as extra credit, so keep it short.
Saved on this device. Show Mr. Mendoza or add these to your notebook glossary to claim the extra credit.
Hand-picked readings and interactives for this lesson, from authoritative open organizations and PLTW's own public course outline.
Check yourself · commit, then reveal▸
Claim ceiling for this check: The supplied lesson evidence can support an observation, pattern, classroom mechanism, or next-step decision about Design justification CER. It cannot by itself prove causation, establish a real clinical diagnosis, or justify action outside this classroom task.
A team writes: 'We added a big open-clinic button because it looks clean and modern.' Rewrite this as a real design justification.
Write an answer and pick a confidence to unlock the key.
Fast retrieval with instant answers, not the commit-then-reveal check above. Try each from memory first: write what you remember about the earlier units, then check yourself here.
Go further and get help▸
What today's skills lead to. These are real health-science careers this course builds toward. Tap one to see, on the US Department of Labor's O*NET site, what the job actually involves, what it pays, and how fast it is growing.
Today is individual work you can do from home: complete the same target above, then submit your CER.
Open the drop folderTurn this in at the drop folder with your district Microsoft sign-in, or hand it to Mr. Mendoza in class. Both count as submitted. Doing the activity in myPLTW does not.
Class still runs. Complete the online activity above (it's self-guided). Need the concept taught without a teacher? Use this authoritative explainer:
Ready.gov: pandemic and large-scale health emergenciesYou've passed Unit 2, so the optional extra-credit track is open. Complete reserved-unit work from home, including virtual labs, for extra credit. Each item shows its correct submission route.
Open the extra-credit track- CompleteEvery required part of the artifact is present, nothing left blank.
- AccurateThe science and the data are correct and match the evidence.
- Scientific reasoningYou explain your claim with evidence and reasoning (CER), not just an answer.
- Professional communicationClear, organized, labeled, and written the way a clinician or scientist would.
- SubmittedTurned in the right way, on the class site or handed to Mr. Mendoza in class, and confirmed. Not in Schoology: that is where the report-card grade appears later.