This video changed how we teach. It might change how you teach, too.

In 2006, Stenhouse Publishers filmed us teaching a whole-group lesson. Yes, the classroom and clothes look dated. But what you're about to see is timeless.

Watch with the sound OFF. That's intentional.

The video starts at minute 5 and runs through minute 7. Watch the students' bodies. Around the 7-minute mark, you'll see it: the head rolls, the ponytail shakes, the face rubbing against the chair, the student lying on the floor.

These are good kids. Engaged kids. Kids who want to learn.

Their brains are full.

Working memory can only hold 3–7 new ideas at once (Miller, 1956; Cowan, 2000). After about 10 minutes of new instruction, students start to disengage—not because they're bored or misbehaving, but because that's how the brain works (Medina, 2008).

See It for Yourself

Film your own lesson. Set up a camera and teach for 10 minutes straight.

Watch it back with the sound off.

You'll see the moment. The head tilts. The pencil tapping. The eyes wandering. The exact second they check out.

When you see it, your teaching changes forever.

You'll stop trying to cover everything in one lesson. You'll start protecting time for students to process, practice, and work with what you just taught them.

That's when the real learning happens.

The Research Behind What You Just Saw

Cowan, N. (2000). The magical number 4 in short-term memory: A reconsideration of mental storage capacity. Behavioral and Brain Sciences, 24(1), 87-114.

Medina, J. (2008). Brain rules: 12 principles for surviving and thriving at work, home, and school. Pear Press.

Miller, G. A. (1956). The magical number seven, plus or minus two: Some limits on our capacity for processing information. Psychological Review, 63(2), 81-97.

Sweller, J. (1988). Cognitive load during problem solving: Effects on learning. Cognitive Science, 12(2), 257-285.