We all know how hard it is to identify the credentials or attributes that might distinguish great teachers from others. Certainly it stumps a lot of researchers, and it is not for lack of trying. Israeli economist Victor Lavy comes at this sticky problem from another angle. Instead of trying to correlate specific teacher characteristics to student achievement, he uses teachers' classroom practices.

Lavy gets an A for his novel approach, but as we learn, classroom practices may be as difficult or impossible to measure as teacher characteristics.

Instead of observing teachers in action to record their instructional practices, Lavy hands the job over to the students themselves, some as young as 10, using a rather sophisticated survey that we couldn't help but think youngsters might find a tad confusing. Though the Gates Foundation's Measures of Effective Teaching Project also makes use of student surveys, the questions are much more age appropriate and student responses serve as only one piece of a much larger puzzle.

Lavy concludes that a teacher's light or moderate use of "traditional" instructional practices (e.g., providing examples to help understand the material and giving memorization exercises) and frequent use of "modern" instructional practices (e.g., giving assignments whose answers haven't been covered in class or text books and expecting students to evaluate their own answers) yield the greatest benefit to students. Surprise--both traditional mastery of content knowledge and modern pursuit of deep and self-directed inquiry turn out to have their place in the classroom. Quasi-provoking at best.