The following post is one of a small group I have written over the past 13 years that have attracted the most readers. This one originally appeared in 2014. I have revised and updated it.

Over the next month or so, I will revise other posts that have drawn the most viewers.

The dream of more data not only enabling better individual choices but also to measure how productive employees are has accompanied the growth of digital technology. The tacit promise is that the more you know, the better decisions you can make and secure the desired results. Reams of data spill forth at the click of a cursor to help each of us decide on a job, buy a home, go to college and whether to get that fascinating gadget. And measuring productivity is also common among corporate employers, be they Apple, Amazon, and Google, baseball managers, or on a humbler level, even school district superintendents and principals.

In the quest to determine how much work employees do at their jobs, some companies use “bossware.” Software programs track the strokes employees make on their computer keyboards (see here and here). Managers monitoring who their staff interact with including clients and colleagues try to measure how productive they are. Call center employees, financial consultants, and accountants have become familiar with “bossware.”

Has such digital oversight, however, invaded schools and classrooms?

The short answer is “not yet.” The longer answer is a “maybe” accompanied by a raft of ongoing initiatives to track both teachers and principals in their daily activities and interactions with students including proposals to place cameras in classrooms (see here).

But measuring teacher productivity is a far tougher task than digital enthusiasts initially thought. Consider that once the teacher closes her door, the classroom becomes unknown to outsiders. It is a black box to district supervisors, building principals, and parents. As a result, many district leaders, site-principals, and researchers have to depend upon teacher self-reports, including logs, of their planning activities and classroom practices. Such teacher surveys and logs are helpful but they are self-reports vulnerable to skewed estimates. Thus, the gold standard for determining teacher productivity remains direct observation of lessons using protocols that are both reliable and valid.

But school principals do not spend most of their time sitting in classrooms observing their teachers. If a school of 500 students, for example, has 25 classroom teachers, the principal, who is expected to manage the school’s entire staff, meets with parents and even occasionally teaches a lesson while reporting to her district supervisor— has barely enough time to visit the bathroom. So it is no surprise that any single teacher in the school sees her principal no more than once or twice in her classroom during the 36-week school year. And for that district curriculum specialist in math or social studies, it would be closer to once every few years.

Teachers-observing-other teachers or peer observation does occur in a few districts but remains a seldom used practice across the nation’s schools. Moreover, the primary point of peer observation is not to determine productivity nor evaluate performance; it is to offer colleagues varied ways of approaching lessons.

Such infrequency of classroom observation of lessons makes directly measuring a teacher’s productiveness, nearly impossible. Yet even were weekly or monthly observations of classroom lessons possible (and, given the current structure of schooling, this is hypothetical, distant from the reality existing in U.S. schools) what measures would one look for to assess a teacher’s productivity?

Consider the following list of possible measures to get at teacher productivity:

*Student test scores on district and test tests (providing such tests measured the curriculum that teachers taught).

*Percentage of student homework turned in;

*Hours teachers spent planning lessons, classroom teaching, and assessing student work;

*Degree to which students interact with teachers before, during, and after lessons;

*Students and teachers’ perceptions of classroom climate in which lessons are taught;

The above measures combine actual products of teaching (the first two) and the process of teaching (final three). To get at teacher productivity, then, one needs to consider both what teachers do before, during, and after their lessons and what work students produce along with their perceptions of their teachers.

Teacher productivity, then, is linked to measurable student outcomes. Of course, teacher effects on students’ goals, effort, and attitudes toward learning–important outcomes surely connected to teacher actions–are missing from this list because reliable and valid measures of these outcomes are seldom used in schools and districts to assess teacher productivity.

So, in light of the above difficulties, is it a fool’s errand to measure how productive teachers are in teaching lessons? Frequent readers of this blog know that my answer will be “no” to this rhetorical question.

And I say “no” because not only do administrators want to know about how productive their teachers are but so too do parents and taxpayers want that information. But most of all, teachers themselves want to know.

Each teacher already has a sense of their productivity and knows when, and under what circumstances, they hit singles, doubles, triples and homers and when they strike out with their students. Teachers know well that they have some influence, even control, over their 20-30 elementary school students they see for six hours daily (out of the 16-18 they spend at home) and the 125 students that high school teachers see for an hour or so each day; but that influence and control are limited not only because they see students a small portion of the day but also because teachers depend completely upon their students for learning to occur.

Thus, teacher productivity is one factor among many that shape what and how students learn. It is important for teachers, administrators, and parents to gather such data and assess that productivity to grasp the question of effectiveness. Measuring teacher productivity, then, is not a fool’s errand.