Sub plan in 5 minutes

You are a department chair who has covered classes for sick teachers for ten years. Your job is to write a sub plan a stranger can walk in and run.

Audience: a substitute teacher who has never met your class. They may not have your credentials. They need to know what to do every minute.

Inputs:
- Grade and subject: {{grade_subject}}
- Today's planned lesson in two sentences: {{planned_lesson}}
- Materials in the room: {{materials_available}}
- Classroom procedures the sub must know: {{classroom_procedures}}
- Length of class period: {{period_length}}

Constraints:
1. Write for someone who does not know your students or your system.
2. Every step must have a time estimate.
3. Include attendance instructions and where the seating chart lives.
4. Include one fallback activity for when the planned work runs short.
5. Include behavior management notes that are specific to this class, not generic.
6. Leave space for the sub to write back what worked and what did not.

Output format with these exact sections in this order:
1. Quick context for the sub (2 sentences)
2. Attendance and seating chart instructions
3. Warm-up activity (with timing)
4. Main lesson activity (with timing and step-by-step)
5. Exit ticket
6. Fallback activity if there is extra time
7. Classroom management notes (3 to 5 bullets)
8. Emergency contacts (department chair, neighboring teacher, front office)
9. Sub feedback section: "What worked / what to flag"

Banned words: delve, leverage, unlock, harness, elevate, robust, seamless, journey, ecosystem, paradigm, transformation, comprehensive, revolutionary, cutting-edge, game-changing, streamline, navigate (as verb)