Coating ratio CER

Open your materials, follow the steps, then turn in your work.

Design your own ratio trial, then write a CER recommending a coating ratio against the five-to-six-minute window.

2. Start the work

State the target precisely: intact through the stomach phase, then fully separated from the coverslip between five and six minutes.

Show all 6 required steps
  1. State the target precisely: intact through the stomach phase, then fully separated from the coverslip between five and six minutes.
  2. Choose which polymer ratios you will test and how many, and write down why.
  3. Write your operational definition of fully separated before you run anything, and how you will time it.
  4. Decide whether you will repeat each ratio, and how many times.
  5. Run the trials and record on the data sheet.
  6. Write the CER: your recommended ratio, the data that supports it, and the reasoning that connects them.

Lost your place? Reopen today's Coating ratio CER record. Find the last completed evidence ID, check it against the claim ceiling, and continue with the first unfinished step rather than restarting the whole task.

Check your work before submitting

  • Change one variable at a time so a result can be attributed to the ratio.
  • Recommend a ratio against the window, not against the fastest time.

3. Turn in your work

DueCheck Schoology
Hand in
CER stating whether the prototype met its design goal, citing averaged trial data and variable-control evidence, explaining design strengths and flaws, proposing a specific iteration with a predicted result, and stating test-data limitations.
How to submit and name your file

Use the submission route shown on today's today's page.

In Schoology, open your course and the assignment for this lesson. Attach your file, select Submit, and check that it appears in the submission.

PDF upload help

You get two school days for every day you were absent, so this deadline moves with you.

How this lesson connects

Keep using what you learned last class: An interval you skipped is data you cannot get back, so the discipline of the interval is what makes the run usable. Today: A biomedical design advances when test evidence is compared with explicit user needs, criteria, constraints, risks, and failure modes, then used to justify a documented revision.

Print or open for todayActivity 4.1.5 Drug Design Lab

Check you have the right sheet: the top of it prints today's portal day, Coating ratio CER. The PLTW activity itself is in myPLTW and is not posted here.

Unit 4 extra creditNine items, any order, turn one in any day. Read the cover sheet first.Cover sheet (6 pages)See all nine
Optional: listen or watch a unit review
Optional unit study notebook
Designing a biomedical innovation: finding a real need, the design process, medical devices and sensors, and prototyping a solution.
Open the notebook
Optional review video
Video overview
Need help? Warm-up, timing, and directions

💡 Big idea: A biomedical design advances when test evidence is compared with explicit user needs, criteria, constraints, risks, and failure modes, then used to justify a documented revision.

  1. 0-8 minReview Wednesday : confirm average performance and trial variability.
  2. 8-20 minWrite the claim: one sentence stating whether the prototype met its design goal.
  3. 20-42 minWrite evidence: cite average trial data, controlled variables, and one variability observation.
  4. 42-58 minWrite reasoning: link data to design strengths and flaws.
  5. 58-70 minWrite the iteration proposal (one variable to change, predicted outcome) and test-data limitations.
  6. 70-80 min: confirm claim addresses the design goal, data is cited specifically, iteration predicts a result.
Mr. Mendoza's 5-minute intro
  • You collected the data Wednesday; now you write the formal argument about what it means for the device design.
  • The claim must address the design goal directly: did the prototype meet the specification or not?
  • The iteration you propose is the most practically valuable part of this CER: it says what you would do next.
  • Your limitation should explain why the Wednesday data might not generalize to a real clinical use case.
Know by the end
  • A prototype evaluation CER claim states whether the device met the specified design goal, not whether it was 'good.'
  • Trial data is the primary evidence: average performance and trial-to-trial variability both belong in the evidence section.
  • An iteration proposal changes one variable based on the data; it should predict what the next trial result will be.

PLTW connection and today's work

Open myPLTW and find Lesson 4.1 Designing the Future, Activity 4.1.5 Drug Design Lab Part II, and use its analysis prompts as a writing scaffold.

Today's stopping point: Platform prompts done in first 10 minutes; full CER submitted before end of period.

PLTW activity titles identify the course connection. If your account will not open, use the posted materials for today and tell Mr. Mendoza. Do not mark an online activity complete unless you completed it.

Course connection

  • Activity 4.1.5 Drug Design Lab
Open Activity 4.1.5 Drug Design Lab in myPLTW

Use the turn-in directions at the top of this page. Do not create a second submission unless your teacher asks for one.

Show another explanation or a smaller first step

Need help? Choose a starting point

Need a running start
Sort today's statements about Coating ratio CER into observation, teaching model, and decision before writing a claim.
On track
Complete the assigned CER stating whether the prototype met its design goal, citing averaged trial data and variable-control evidence, explaining design strengths and flaws, proposing a specific iteration with a predicted result, and stating test-data limitations., cite at least two evidence IDs, apply the reviewed rule, and name one limitation.
Stuck? Get unstuck
Use the sentence frame: E1 shows ____. E2 helps explain ____. Therefore I can claim ____, but I cannot claim ____.
Push me further
Identify one additional measurement, control, or stakeholder perspective that could change the decision, then explain exactly how it would change the claim level.
Lesson resources: reading, slides, and vocabulary
Socratic teaching slide deck

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.

Carry forward

An interval you skipped is data you cannot get back, so the discipline of the interval is what makes the run usable.

Daily take-home

A biomedical design advances when test evidence is compared with explicit user needs, criteria, constraints, risks, and failure modes, then used to justify a documented revision.

Inspect the analogy

An engineering team tests one prototype feature at a time against a written criterion and records each failure before revising.

  1. Which criterion is being tested?
  2. What stays controlled between trials?
  3. Which result justifies a specific revision?
Rule

A useful prototype test links a controlled trial to a measurable criterion and turns the result into a documented revision decision.

Where it breaks

A classroom test can reveal a design weakness without establishing clinical , effectiveness, durability, or regulatory readiness.

Map the analogy to biology
  • The written criterion maps to the pass condition.
  • Repeated controlled trials map to test evidence.
  • The revision log maps to the next design change and its rationale.
Read this first

Driving question: Design your own ratio trial, then write a CER recommending a coating ratio against the five-to-six-minute window.

What you already know: An interval you skipped is data you cannot get back, so the discipline of the interval is what makes the run usable.

New idea: A biomedical design advances when test evidence is compared with explicit user needs, criteria, constraints, risks, and failure modes, then used to justify a documented revision.

Visual or model: F1. F1. A lesson illustration or teaching diagram for Coating ratio 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.

  1. Observe or measure the relevant feature in coating ratio CER.
  2. Organize the observation with a stable evidence ID.
  3. Apply this rule: A useful prototype test links a controlled trial to a measurable criterion and turns the result into a documented revision decision.
  4. Choose the option the evidence supports and state the limit of the conclusion.

Real biomedical example: Today the biomedical investigation team uses Coating ratio CER to make a bounded evidence decision. A classroom prototype, , presentation, or does not establish clinical , effectiveness, manufacturing quality, or regulatory clearance.

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.

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.

Evidence set and decision
E1 · Source fact

U.S. Food and Drug Administration is the source this lesson's claim is checked against: Design Controls

Limit: A classroom prototype, , presentation, or does not establish clinical , effectiveness, manufacturing quality, or regulatory clearance.

E2 · Teaching model

A useful prototype test links a controlled trial to a measurable criterion and turns the result into a documented revision decision.

Limit: A classroom test can reveal a design weakness without establishing clinical , effectiveness, durability, or regulatory readiness.

E3 · Task criterion

Change one variable at a time so a result can be attributed to the ratio.

Limit: E3 defines the classroom product or success criterion. It is not independent scientific evidence and cannot justify a clinical or causal claim.

PLTW-PBT-2026-12-17 · Simulated classroom evidence scenario

Your role: biomedical investigator

Decision: Your team must decide what the evidence from coating ratio CER supports before submitting the claim-evidence-reasoning response named on today's page.

  • Recommend the device for real patients if it meets the criteria in class, since that is what a successful test means.
  • Collect the missing failure-mode data before proposing an iteration, since the trials never tested how this device fails.
  • Judge the prototype against the trial data and the stated criteria, then propose the one iteration that evidence supports.

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: Today's evidence supports a classroom claim about coating ratio CER. It cannot prove causation, diagnose a real patient, or justify action outside this room.

Composite case file · PLTW-PBT-2026-12-17

Reason for review: Your team must decide what the evidence from coating ratio CER supports before submitting the claim-evidence-reasoning response named on today's page.

Context: Today the biomedical investigation team uses Coating ratio CER to make a bounded evidence decision. A classroom prototype, , presentation, or does not establish clinical , effectiveness, manufacturing quality, or regulatory clearance.

Timeline:
  • T1: State the target precisely: intact through the stomach phase, then fully separated from the coverslip between five and six minutes.
  • T2: Choose which polymer ratios you will test and how many, and write down why.
  • T3: Write your of fully separated before you run anything, and how you will time it.
  • T4: Decide whether you will repeat each ratio, and how many times.
  • T5: Run the trials and record on the data sheet.
  • T6: Write the CER: your recommended ratio, the data that supports it, and the reasoning that connects them.
Evidence records:
  • E1: U.S. Food and Drug Administration is the source this lesson's claim is checked against: Design Controls
  • E2: A useful prototype test links a controlled trial to a measurable criterion and turns the result into a documented revision decision.
  • E3: Change one variable at a time so a result can be attributed to the ratio.

Measurements: Use only the measurements, units, graph, or counts supplied in today's task. No additional patient measurement is implied.

Figure finding: Teaching diagram for Coating ratio CER. Trace the labeled observation or evidence sequence before choosing an explanation. This is a teaching model, not patient or experimental data.

Uncertainty: This is a composite classroom scenario. Missing history, measurements, or confirmation tests remain unknown and limit the conclusion.

Math moment
Formula or setup

Mean = sum of values / number of values. Median = middle ordered value. Range = maximum - minimum.

Worked parallel example

For 2, 4, 4, and 10: mean = 20 / 4 = 5, median = 4, and range = 10 - 2 = 8.

Units and reasonableness

Mean, median, and range keep the measurement unit. Order the values before finding the median.

Try it with today's data

Calculate the requested summary for today's supplied values, then write what it reveals and what it hides.

Design record
Criteria
  • The solution must address the stated need in coating ratio CER.
  • The decision must be supported by E1-E3.
  • The final product must make the success criteria visible.
Constraints
  • 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.
Tradeoff weights
  • 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.

Iteration log
  1. Version or option tested
  2. Criterion met or missed
  3. Evidence ID and result
  4. Revision made
  5. Reason for the revision
Decision record
  1. Need and user
  2. Criteria and constraints
  3. Chosen option and evidence
  4. Test result
  5. Revision and reason
Watch the trap

Students often think A polished answer about Coating ratio CER is trustworthy even when its evidence source, comparison, or limitation is missing.. The trap: Presentation quality cannot raise the evidence level. A classroom prototype, , presentation, or does not establish clinical , effectiveness, manufacturing quality, or regulatory clearance.

Worked example · a parallel case (guides, does not reveal)
Non-answer evidence and reasoning scaffold
Completes: A blank structure for organizing the assigned response. It contains no claim, ranking, calculation, data interpretation, or recommendation from today's task.

1. Decision or claim I am testing: ____

2. Evidence ID and exact observation: ____

3. Second evidence ID and exact observation: ____

4. Rule that connects the evidence to my claim: ____

5. Strongest alternative or tradeoff: ____

6. Limitation or missing evidence that controls my confidence: ____

7. Revision I would make if the missing evidence changed: ____

Why this matters

This model shows the level of evidence and organization needed to complete: A blank structure for organizing the assigned response. It contains no claim, ranking, calculation, data interpretation, or recommendation from today's task.

Build yours step by step
  1. Write one defensible claim.
  2. Choose specific evidence that supports the claim.
  3. Explain the scientific rule that connects the evidence to the claim.
Change it for a new task

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 Schoology before end of period.

See the full worked example
Portal terms
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.
Audio Resources

Play the cold open at the start of the unit to set the scene. Each recording is AI-generated and simulated (fictional callers, no real people or student data).

PBS U4 - Client design-brief voicemailActivity 4.1.1 Open for InnovationBlock 1 cold open
Resources & readings

Hand-picked readings and interactives for this lesson, from authoritative open organizations and PLTW's own public course outline.

Practice: try a question, then check your answer

Claim ceiling for this check: Today's evidence supports a classroom claim about coating ratio CER. It cannot prove causation, diagnose a real patient, or justify action outside this room.

Quick self-check · commit, then reveal

A student makes a certain conclusion about Coating ratio CER from one classroom result. What must the student add before the conclusion is defensible?

How sure are you?

Write an answer and pick a confidence to unlock the key.

Missed class or ready for more?
🔬 Pre-lab simulation

Run this before you touch the bench. It is built from the real lab procedure, so the decisions you make here are the ones you will make with the equipment in your hands.

It Was Inert in the Beaker
Open the simulation →
Where this leads: careers
What to do if you were absent
If YOU are absent

Today is individual work you can do from home: complete the same target above, then submit your CER.

FOR A GRADE
Open Schoology

Go to Schoology to turn this in. Submit one PDF. Put your first and last name in the document header. Name the file: FirstName LastName - Assignment Title - YYYY-MM-DD.pdf. If you cannot get in, see Mr. Mendoza. Do not skip the work.

If MR. MENDOZA is absent

Class still runs. Complete the online activity above (it's self-guided). Need the concept taught without a teacher? Use this authoritative explainer:

PhET: simulations for engineering and physical testing
Optional extra credit (async)

You'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
How this is graded
For: CER: CER stating whether the prototype met its design goal, citing averaged trial data and variable-control evidence, explaining design strengths and flaws, proposing a specific iteration with a predicted result, and stating test-data limitations.
  • Complete
    Every required part of the artifact is present, nothing left blank.
  • Accurate
    The science and the data are correct and match the evidence.
  • Scientific reasoning
    You explain your claim with evidence and reasoning (CER), not just an answer.
  • Professional communication
    Clear, organized, labeled, and written the way a clinician or scientist would.
  • Submitted
    Go to Schoology to turn this in. Submit one PDF. Put your first and last name in the document header. Name the file: FirstName LastName - Assignment Title - YYYY-MM-DD.pdf. If you cannot get in, see Mr. Mendoza. Do not skip the work.