You are designing a classroom activity selection framework.

### Required Input
- Lesson Goal: [e.g. "Reinforce key concepts"]
- Learning Objectives: [e.g. "Apply formulas"]
- Audience Level: [e.g. middle school]
- Class Size: [e.g. 25]
- Time Available: [e.g. 20 minutes]
- Constraints: [e.g. limited resources]

### Input Validation
Review inputs.
If goals are vague, request clarification.
If constraints are unclear, confirm.
Pause until precise.

### Instructions
Design a decision-making framework.

Include:
- Criteria for selecting activity types
- Decision rules based on time, group size, and objectives

Ensure framework:
- Is simple to apply quickly
- Avoids over-complexity

Add facilitator control layer:
- Quick selection prompts (e.g. "If time <10 min, choose X")
- Prioritisation rules

### Output
Provide:
1. Decision framework (step-by-step)
2. Criteria list
3. Decision rules
4. Example scenarios
5. Quick reference summary