How Should Teachers Be Evaluated?

In football, the quarterback is the leader of the field. He is involved in almost every offensive play and is paramount the team's success. Every year college and professional teams spend millions to secure and protect their quarterback. But how do teams appraise the value of a quarterback? In other words, with so much riding on a quality quarterback, how do teams quantify the effectiveness of the quarterback? In the National Football League, there is a statistic called Passer Rating. This score is an aggregation of statistics (i.e., passing yards, touchdowns, completions, and interceptions) with a specific weight. This measure is a decent metric for measuring quarterback's passing ability. For example, Steve Young, a hall of fame player and Superbowl Champion, holds the record for highest career passer rating. It should be noted though that, for passing alone, this is an imperfect metric, and for measuring the whole value of a quarterback (e.g., leadership, courage, decision-making, and running ability), passer rating is quite insufficient.

The outstanding point of my quarterback commentary is to accentuate the importance and difficulty of measuring the complexity of human performance. Like the quarterback, the teacher of a classroom and is the leader and plays a pivotal role in the academic and social-emotional development of each student. The evaluation of teachers is equally difficult, but there is much more at stake than the success of a sports team.

Below is a link for a NYT article that addresses the elusive metric for assessing teacher effectiveness. The article raises the question, but does a poor job of suggesting possibilities.
How Should Teachers Be Evaluated?

Maybe we should take a page from the NFL. Could an Educator Rating be adapted from several sources of information (e.g., student evaluation, third-party observations, student score improvement, and a school climate measure)? From lessons learned in baseball and football, it is unlikely that this composite score would appraise all teachers perfectly and fairly. It may, however, be a more objective, accurate, and agreeable than the current methods used today.

Just food for thought. If you're curious, the NFL passer rating is below:

Then use the above calculations to complete the passer rating: