You can't iterate on a lesson you don't have data about. The agile teaching loop depends on one thing above everything else: accurate, timely information about what students actually understood — not what the teacher thinks they understood based on the hands that went up.
Most classroom assessment collects the wrong data, collects it too slowly, or collects it in a form that can't be acted on until next week. This cluster fixes that. Three articles covering the three practices that produce accurate student data in under 5 minutes every lesson — and the same-day action workflow that connects that data directly to tomorrow's teaching.
C3 is the data collection layer that feeds C4 (iteration) and C8 (AI tools). Everything in the agile teaching loop starts here.