One compelling piece of the evidence comes from data gathered during the PISA test of student performance around the world. Using information on school practices, Elizabeth Green has identified an important difference in how countries organize the work of teaching:
How much time do teachers spend on classroom instruction, and how much time do they have outside of class to devote to the other considerable, less visible aspects of the job: lesson planning, paper grading, conferring with students, calling parents, meeting with colleagues to discuss methods and goals.
Here, the PISA results are not ambiguous. Every single country that outperforms us has significantly smaller teacher workloads. Indeed, on the scale of time devoted by teachers to in-class instruction annually, the United States is off the charts.
We spend far more hours in the classroom on average, twice and nearly three times more in some cases, than teachers in any other OECD country save Chile.
Finnish high-school teachers, for example, clock 553 hours in the classroom each year. In Japan, home of jugyokenkyu [lesson study], that number is 500. In the U.S., it’s 1,051. (Figures for elementary and middle school show roughly the same skew.)The whole article deserves a careful read, and so does Elizabeth Green's new book, Building a Better Teacher.