Value Added is No Magic: Assessing Teacher Effectiveness
That old sorcerer has vanished
And for once has gone away!
Spirits called by him, now banished,
My commands shall soon obey.
In Goethe's classic, the apprentice uses a sorcerer's spell to ease his daily chores. Chanting the master's words, he brings a broomstick to life and tells it to fetch water to clean the workshop. The broomstick obeys, only too well. It races between the well and back until the workshop begins to flood. Although the apprentice had enough knowledge to set magic in motion, he could not think ahead to what he did not know.
I worry about a similar flood of unintended consequences if the Los Angeles Times moves forward with its plans to publish a database that places 6,000 Los Angeles third- to fifth-grade teachers on a spectrum from "least effective" to "most effective." The Times believes that the data will be a powerful tool to force better teaching, but it cannot anticipate all of the consequences. For example, consider that capable prospective teachers might avoid a profession in which they risk public embarrassment based on an undeveloped science. Consider the well-documented estimates