DT
IB Design Technology
SL · Lesson 48 · IA Day 18 — Criterion D Audit and Finish
01 / 09
Lesson 48 · Unit 6

IA Day 18 —
Criterion D Audit & Finish

Assemble the development story: multiple testing/refinement cycles plus comprehensive formal drawings of the intended solution.

80 minutesIA Criterion D
Guiding question: Does Criterion D show a developed solution—or only a collection of model photos?01
Today’s destination

By the end of class, you should be able to…

01

Audit development evidence

Make multiple model-test-refine cycles obvious.

02

Audit testing breadth

Ensure all specifications and intended-user needs are addressed.

03

Audit drawings

Check formal manufacturer-facing communication.

04

Finish Criterion D

Convert scattered evidence into a coherent design-development story.

Success check: Produce clear, criterion-aligned IA evidence during today’s studio block.
IA DAY 18 · Criterion D finish02
≈6
Development

Fidelity-model cycles

Annotated drawings/photos/CAD showing model → test → refine through intended-user testing.

≈4
Communication

Formal drawings

Assembled, exploded and orthographic drawings with dimensions, proportions and assembly.

300
Recommended

Words

Criterion D is highly visual; concise written explanation supports the evidence.

10
Annotation

Words max each

Longer annotations are treated as descriptive text for word-count purposes.

Criterion D · approximate evidence shape03
Selected ideaFrom Criterion C.
Model v1 + testExpose a major issue.
Refine + model v2Evidence-based change.
Retest + refineAddress remaining specifications.
Intended solutionFormal drawings communicate the result.
Criterion D · development, not photo dump04

Model photos only

Images without test evidence or analysis do not show development.

One test cycle

Criterion D expects multiple testing and refinement cycles.

Missing user

User-related requirements need intended-user testing/evidence where appropriate.

Pretty render only

Formal manufacturing drawings still need dimensions, components and assembly.

Audit the evidence—not the decoration05
Physical fidelity model
Built and used for testing/evaluation.
Required
Multiple cycles
Model → test → refine is visible more than once.
D
All specifications
Testing/evaluation addresses the full design specification.
D
Intended-user needs
Testing includes the intended user where relevant.
D
Formal drawing set
Assembled + exploded + orthographic + dimensions/proportions/assembly.
D
Annotations concise
Visual evidence is readable and annotations stay within the rule.
IA
Criterion D · final audit06
Studio block

The mini-lesson is short. The evidence-making is the lesson.

60+minutes work
Repair missing links
Add the test/result/refinement connection beside the relevant visual.
Close specification gaps
Use genuine evidence; acknowledge model limitations honestly.
Finish formal drawings
Check dimensions, components, assembly and manufacturer readability.
Export a clean D draft
Keep image resolution and text legibility high enough for assessment.
IA studio · finish D07

Criterion D answers: “How did the solution become good enough?”

Criterion E answers: “What is the intended redesign solution, what are its key features, and how does it improve on the original product?”

Next: present the intended redesign08
Exit ticket

Before you leave…

1. Identify the clearest model-test-refine cycle in your D pages.
2. Name the weakest evidence link you repaired today.
3. Confirm the formal drawing set communicates to a third-party manufacturer.
Next lesson

IA Day 19 — Criterion E: Present the Intended Solution

Keep the evidence chain moving: user → research → decision → test.

Curriculum alignment
Criterion D evidence: annotated visual evidence of multiple testing/refinement cycles through intended-user testing, approximately six A4 pages or equivalent; formal assembled, exploded and orthographic annotated drawings with dimensions, proportions and assembly, approximately four A4 pages or equivalent; recommended Criterion D word count 300; physical fidelity model required for the design project.
Lesson complete9 slides
Designed by David Xu · © 2026 David Xu. All rights reserved.Educators and students are welcome to use these materials for non-commercial teaching and learning with attribution. Please share the original link when possible. Reposting, redistributing modified copies, removing attribution, or commercial use requires prior permission.
IB Design Technology SL · Lesson 4809