Lesson 45 · Unit 6
IA Day 15 —
Refine & Retest · Cycle 2
Make the second model visibly smarter than the first by linking each change to evidence from testing.
80 minutesIA Criterion D · B2.1.12
Change
Retest
Compare
Guiding question: How can a second model prove that iteration—not decoration—improved the redesign?01
Today’s destination
By the end of class, you should be able to…
01
Turn evidence into change
Every meaningful refinement should have a reason.
02
Retest the change
Do not assume the refinement solved the issue.
03
Compare v1 and v2
Show how performance/user experience changed.
04
Find remaining gaps
Prepare for testing against all specifications.
Success check: Produce clear, criterion-aligned IA evidence during today’s studio block.
IA DAY 15 · Cycle 202
Evidence v1What failed / underperformed?
Design decisionWhat feature will change?
Model v2Build the refined feature.
RetestUse the same or improved test.
CompareDid the change improve the result?
Iteration = evidence → change → retest03
Knowledge check
Which change best demonstrates iterative development?
Refinement changes the design because evidence demands it04
| Version | Evidence | Change made | Specification | Retest result |
|---|---|---|---|---|
| v1 → v2 | Observed / measured issue | Specific feature change | S# | Better? Same? New issue? |
| v2 → v3 | Next evidence | Next refinement | S# | Result |
The log is a thinking tool. Your final Criterion D pages still need clear visual evidence of the development cycles—not only a table.
Make the development traceable05
Studio block
The mini-lesson is short. The evidence-making is the lesson.
60+minutes work
Apply v1 refinements
Modify the model based on actual evidence.
Modify the model based on actual evidence.
Retest v2
Repeat the relevant task/test so comparison is meaningful.
Repeat the relevant task/test so comparison is meaningful.
Capture before/after evidence
Photograph / draw / export the versions and results.
Photograph / draw / export the versions and results.
Write the next decision
Continue the cycle if a major requirement remains unresolved.
Continue the cycle if a major requirement remains unresolved.
IA studio · refine → retest06
Change has a cause
Evidence from v1 is visible.
CauseEvidence from v1 is visible.
v2 is genuinely different
The redesign—not just the presentation—changed.
RefineThe redesign—not just the presentation—changed.
Retest happened
The improvement is checked, not assumed.
TestThe improvement is checked, not assumed.
Comparison is explicit
The reader can see whether performance/user experience improved.
AnalyseThe reader can see whether performance/user experience improved.
Criterion D · evidence of iteration07
Exit ticket
Before you leave…
1. Identify the evidence that caused today’s biggest refinement.
2. Explain how v2 changed relative to v1.
3. Name a specification that still has weak or missing evidence.
Next lesson
IA Day 16 — Testing Against All Specifications
Keep the evidence chain moving: user → research → decision → test.
Curriculum alignment
IA Criterion D: iterative fidelity models through multiple testing and refinement cycles; align with design specifications and intended-user needs. B2.1.12: demonstrate iterative development using the model-test-refine cycle.
IA Criterion D: iterative fidelity models through multiple testing and refinement cycles; align with design specifications and intended-user needs. B2.1.12: demonstrate iterative development using the model-test-refine cycle.
Lesson complete8 slides
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IB Design Technology SL · Lesson 4508