Gates-funded teacher evaluation study sheds light on Chicago system

January 8, 2013

A report released Tuesday by the Bill & Melinda Gates Foundation suggests that Chicago’s new teacher evaluation system may be on the right track in helping to determine which teachers are most effective.

Through studies in seven school districts, researchers from 21 universities and organizations put teacher observations, student achievement gains and feedback from student surveys under a microscope—and found these measures were accurate.

Researchers randomly assigned students to math and English teachers who had already received better or worse ratings based on the measures. They got proof the ratings worked when, after a year, students did better or worse according to which teacher taught them.

“As a group, teachers previously identified as more effective caused students to learn more. Teachers identified as less effective caused students to learn less,” says the report. (Read more about the study here.)

Researchers note that one goal is to have a rating system that doesn’t fluctuate too much from year to year, and also predicts students’ performance on state tests and higher-level tests.

They accomplished that using formulas that put 33 percent to 50 percent of the weight on the growth in students’ state test scores, and split the rest of the ratings equally between teacher observations and student survey results.

CPS plan not an exact fit

CPS’ plan bears some similarities, but doesn’t fit the model exactly. Teachers this year will have 75 percent to 90 percent of their evaluations determined by observations of teacher practice. The percentage of evaluations tied to student growth will be 10 to 25 percent, but will increase to up to 30 percent for some teachers in the 2014-2015 school year, then to 35 and perhaps 40 percent in subsequent years. The percentage will include district-designed “performance tasks” as well as standardized tests.

In addition, the research cautions that teachers should be observed at least twice, by at least two different observers, in order to create an accurate rating. CPS teachers are to be observed at least four times when they are evaluated, but there is no guarantee different administrators – such as an assistant principal and the principal – will carry out those evaluations.

"The configuration of an observation schedule is made at the school level and in many cases, both administrators are conducting observations," notes CPS spokeswoman Robyn Ziegler. Some schools also have several assistant principals, meaning some teachers could be observed by three or more different administrators.

CPS and the Chicago Teachers Union are also studying the issue of student surveys. The district will pilot the surveys in 2013-2014, and a joint union-CPS committee will decide whether to include them in teacher evaluations during the 2014-2015 school year. Originally, the district planned to make surveys 10 percent of teachers’ evaluations, but that plan was scrapped during this fall’s teacher strike.

Jean Clements, president of Florida’s Hillsborough Classroom Teachers Association, said on a press call announcing the study results that surveys aren’t part of her district’s evaluation process because they were thought to be most contentious of all.

“We can use the student surveys to improve practice without bringing it into the actual evaluation process, which we think would be controversial and a bit contentious,” Clements said.