How A C-Rated School Can Be Full of Effective Teachers

The Florida Senate

Florida Senate President Don Gaetz wondered how low-rated schools could be full of teachers earned positive evaluations.

Last month Senate president Don Gaetz raised eyebrows when he questioned the accuracy of Florida’s new teacher evaluations.

The evaluations are based on a complex statistical formula which weighs Florida Comprehensive Assessment Test scores and other factors to calculate how much a teacher influences student learning. The evaluations will eventually contribute to how much a teacher is paid, despite complaints the results have large margins of error and can change significantly from year to year.

“How can you have a C or D ranked school in which 85 percent, or 90 or 95 percent of the teachers are classified as effective or highly effective?” Gaetz told the Associated Press. “It seems to me that those two data points have to have some relationship to each other.”

It’s a question the Tampa Bay Times also looked at on Sunday, asking how Pinellas County schools earning the state’s highest report card grades could have relatively low school-wide teacher evaluation scores?

According to the state’s numbers, Tarpon Springs High, a solid A school, received one of the lowest scores in Pinellas. The score indicates teachers caused students to perform 28 percent worse than like students across Florida.

Palm Harbor University High, ranked the top Pinellas high school by FCAT, was middle-of-the-pack under VAM, although students did make gains. Pinellas Park came out on top.

A minus-0.28 VAM score put well-regarded Thurgood Marshall Fundamental Middle below several C and D schools.

Both school grades and teacher evaluations rely heavily on FCAT scores, right?

Yes, but they use those scores differently, Matthew Di Carlo writes over at The Shanker Blog.

School grades mostly measure absolute performance — how much kids know and how high they score on the test. Evaluations control for how well a student scored the previous year, though, and are more a measure of student progress.

The evaluations are intended to determine whether students met, exceeded or fell short of expectations, based on the statistical model projections.

If school grades and teacher evaluation scores matched, Di Carlo argues, it could be a sign of a flaw in Florida’s system:

Florida’s schools grades are heavily driven by students’ absolute performance levels, while its teacher evaluation ratings are designed to be independent of those levels. Again, both are matters of degree, and there are other reasons to expect to find some level of concentration of “lower-performing” teachers in schools with lower absolute performance scores (e.g., recruitment/retention issues).

That said, Florida’s school and teacher rating systems are, by design, measuring different things. If anything, an extremely strong relationship between the grades and evaluation ratings might be seen as a red flag that the latter are biased. At the very least, validating one by assuming it must match up with the other is, to put it gently, inappropriate.

Di Carlo goes into great depth about how the two systems work, so check out The Shanker blog for more.

It’s also important to remember that some school district evaluations were more forgiving —  intentionally — as they phased in the requirement. Fewer teachers are expected to earn top ratings in future years.

School officials expect lawmakers might revisit the teacher evaluation law during the legislative session beginning March 5.