A recent study found that principals spend only 8% of their time in classrooms. If you have 20 teachers per administrator, that means you’ll see about 0.4% of the instruction in any given class over the course of the year, assuming you spend equal time in each classroom.

Polaroid Land Camera by Flickr user angel_caidoIt’s no wonder that walkthroughs have become a popular way to spot-check what’s happening in schools – when we can see only a tiny fraction of the teaching that takes place, we have to rely on intuitive judgments based on what little we do see.

But we don’t have to just stay for a minute. Perhaps it’s better to spend that 0.4% in 30 or 60-minute chunks, even if you have no intention of doing a formal observation.

When you see a whole lesson, the pieces fit together in a way they don’t when you see only a snapshot.