pbl-arc

# PBL Arc

A pretty poster is not PBL. Lock one **open driving question**, an **authentic audience**, **3–5 milestones** that each teach something just-in-time, and assess **learning** (process + product) so students cannot fake the work with decoration. Explicit instruction lives *inside* the project — not a lecture week followed by a craft week.

Inspired by FW1201/tw-edu-skills tw-edu-pbl-designer (MIT). Copyright (c) 2026 吳奇（奇老師）・數位敘事力社群 (inspiration only). Original English Grok remake. Complements unit-arc (multi-week spine without PBL authenticity), lesson-block (one period), pulse-check (tiny CFU), score-grid (rubric grid), glow-grow (feedback), tier-lesson (same goal / different entry), talk-home (parent conference). Not class-norms. Not need-goal.

Read `references/pbl-rails.md` before you design. Fill the three templates under `templates/`.

## When to use

- Project-based learning / PBL / inquiry project / project brief
- Driving question, authentic audience, public product, sustained investigation
- Milestones with scaffolds and just-in-time teaching points
- Process + product assessment so content beats decoration
- Teacher wants students to *learn through* a project, not only finish a craft

## When NOT to use

- Multi-week unit spine without authentic audience / driving question → unit-arc
- One tomorrow period packet → lesson-block
- Tiny CFU only → pulse-check
- Analytic rubric grid as the main job → score-grid
- Comment on one piece of student work → glow-grow
- Differentiate an already-finished lesson into tiers → tier-lesson
- Parent conference talking points → talk-home
- Classroom community norms / repair scripts → class-norms
- One measurable IEP-style classroom goal → need-goal
- Student exam flashcards → study-loop
- Live exam keys, LMS passwords, student PII, copyrighted curriculum dumps

## Inputs

- Grade band and subject (guess from the ask; confirm only if two subjects collide)
- Topic / content students must learn (required)
- Learning aims in teacher words (what they should know/be able to do)
- Duration (lessons or weeks; default 6–8 lessons / ~3–4 weeks if they said "a project")
- Optional: real local audience, materials/community links, standards codes they already named
- Constraints: class size, language supports, no field trip, shared devices, etc.

## Procedure

1. Read `references/pbl-rails.md`. Refuse clinical BIPs, live keys, student PII, CSAM, self-harm examples, and verbatim curriculum dumps. Hand off: unit-arc (non-PBL unit spine), lesson-block (one day), pulse-check (CFU items), score-grid (rubric grid), glow-grow (one-work feedback), tier-lesson (tiers), talk-home (conference), class-norms (culture), need-goal (one measurable goal), study-loop (exam prep).
2. Decide whether PBL fits. If the aims are mostly isolated factual recall with no application/analysis/communication, say so and offer unit-arc or lesson-block instead — do not force a fake project.
3. Fill `templates/driving-brief.md`. Write one open driving question (no single predetermined answer), a student-facing scenario with a real-or-realistic audience, and the public product. Learning aims must be *required* by the question — students cannot answer well without the intended content.
4. Fill `templates/milestone-map.md`. Break into 3–5 milestones. Each names: deliverable, what must be learned, **just-in-time teacher instruction**, formative check, and a bounded student choice. Instruction is distributed through the arc, not front-loaded then abandoned.
5. Fill `templates/assess-public.md`. Process weight + product weight; content/argument over aesthetics; reflection + revision checkpoint; differentiation notes that keep the same aims. Exclude decoration as a scored criterion unless communication design *is* the standard.
6. Sanity: open question? authentic audience? every milestone teaches? students cannot succeed by copy-paste without understanding? duration fits? No Taiwan-108-only codes unless the teacher asked for that locale.
7. Deliver the three templates. One closing line: this is a PBL arc worksheet; not a generic unit map and not a single-period packet.

## Output format

- Driving brief (question, scenario, audience, public product, aims)
- Milestone map (3–5 milestones with JIT teaching + formative checks + choice)
- Assess-public card (process/product criteria, revision, differentiation)
- One line: PBL arc worksheet; not unit-arc alone and not lesson-block

## Safety

- Follow `references/pbl-rails.md` with no exceptions.
- Education design only. Original student-facing text. No curriculum dumps.
- No student PII. No LMS passwords. No live-test answer keys.
- Age-appropriate. No CSAM. No self-harm examples (crisis → US 988, then stop).
- Not a clinical BIP/FBA. Not legally defensible IEP drafting.
- Not Taiwan-108-only unless the teacher explicitly asked for that locale.

## Stop conditions

- Three templates delivered, or refused for wrong fit (offer unit-arc / lesson-block), copyright dump, integrity (live keys / PII), clinical BIP ask, or handoff to score-grid / talk-home / class-norms / need-goal / study-loop