The Chicago teacher's strike has polarized debate on the controversial topic of teacher evaluation.
On one side of the debate, education reformers say decisions about teacher compensation and job security should be closely tied to the test performance of their students. On the opposite side, teachers and their unions say such evaluations can penalize the best teachers, reduce access to top teachers in poverty-stricken areas, and turn classrooms into places where teaching to the tests trumps true learning.
"Reformers can certainly point to teachers who say that the pressure of standardized testing has been useful, has forced them to pay attention to students they previously ignored, and could rid their schools of lazy and incompetent teachers," said Richard Rothstein, who writes a blog for the Economic Policy Institute.
However, teacher evaluations like those at stake in Chicago create incentives for teachers and schools to narrow the curriculum to tested subjects, Rothstein said. Instruction in history, the sciences, the arts, music, and physical education suffer as a result, and teachers focus less on cooperative activities, character development and social skills, he continued.
Others believe greater teacher accountability for student progress is overdue, especially in Chicago, where teacher salaries are among the nation's highest.
"Those picketing in the streets in Chicago — the teachers, who earn on average, $76,000 per year, and after 30 years in the classroom, receive an annual payment of $77,400 for life, courtesy of the Illinois taxpayer — want to continue receiving this compensation. Moreover, they want it without the accountability that is so badly needed," said the National Review. "That level of compensation, in a district that faces a $1 billion deficit, certainly merits accountability. Teacher evaluations should be based in part on student performance on tests, using a value-added model that takes extraneous factors such as socioeconomic status into account."
Value-added evaluation is a controversial method for measuring teacher success in a given year by comparing student's test scores with their scores from the previous year and figuring in expected improvement. The model links teacher performance to how well their students perform on standardized tests.
In Chicago, older models for teacher evaluations, based mainly on classroom observation, haven't increased teacher accountability, a USA Today editorial said.
"Less than one-half of 1 percent of [Chicago's] teachers were rated unsatisfactory; 94 percent were rated superior or excellent. Yet with all these supposedly fabulous teachers, just 60.6 percent of its students graduated, a dismal percentage that is in line with New York and Los Angeles," said USA Today, citing a 2009 study. "On national reading and math tests, Chicago's fourth- and eighth-graders lagged behind the national average and behind the average even for large urban districts."
But results from value-added teacher evaluation models can be flawed, and can penalize good teachers. Teacher's jobs can rest on the performance of students who were absent during instruction or had a headache or emotional issue on test day. And, the evaluation process gives students who already score near 100 percent proficiency low value-added scores that reflect negatively on good teachers, the Washington Post blog The Answer Sheet said.
Research shows that student achievement is influenced by much more than an individual teacher, but value-added evaluations don't take other factors into account, said Stanford University professor Linda Darling-Hammond during a 2011 briefing to Capitol Hill policymakers.
Those factors can include home-life challenges; student aptitude, health and attendance; peer culture; prior teachers and schooling; and summer-learning loss, which especially affects low-income children. Value-added ratings are significantly affected by differences in the students who are assigned to them, tainting evaluation conclusions, Darling-Hammond said.
Value-added teacher evaluation has a place in increasing teacher accountability, but should be used only in a low-stakes fashion as part of an integrated analysis of what the teacher is doing and who is being taught, Darling-Hammond said.