Decades of research shows that principals can significantly benefit student outcomes, such as grades and college plans.
But what about standardized test scores? A new study suggests that a principal’s impact on test scores is likely much smaller than previously believed.
The study, a working paper published by the Annenberg Institute at Brown University and not yet peer-reviewed, found that existing approaches linking principals to test scores are flawed and attribute to principals effects that aren’t under their control.
“This is not a study that says that principals are not important. Principals are absolutely important,” said Brendan Bartanen, lead author of the study and an assistant professor of education policy at the University of Virginia, in an interview.
Instead, what the study suggests is that “we need to be very careful about trying to infer the performance of a principal on the basis of the [test-score] outcomes of students,” Bartanen added.
Existing research on the topic has used test scores to measure the effectiveness the of certain school leadership policies and practices. For example, one research study found that replacing a below-average principal with someone in the above-average category can add more months of learning in math and in reading during a single school year. Another found that students who attended schools with principals trained by a certain program had slightly higher achievement scores than students who didn’t attend a school with principals in the program.
And principals who spoke with Education Week insisted that they do believe they have a major impact on all student outcomes—and that includes test scores.
“I feel like as the building leader, you’re the person who’s charged with altering the trajectory of a child,” said Ronnie Harvey Jr., the 2022 Louisiana Principal of the Year. “The principal plays a major part in setting the climate and the culture inside of a school building. If the culture of the school is very chaotic—it’s not conducive to learning—that’s gonna play a part in how instruction is given out on that campus.”
“If that tone is not set, then I guarantee there’s going to be a direct correlation seen in outcomes,” Harvey added.
Nearly all states include measures of student progress over time, or what researchers call “value-added” measures, into their principal-evaluation systems. To analyze whether this is an effective metric, Bartanen and his co-authors reviewed data from New York City, Oregon, and Tennessee and compared the variations in student achievement within schools.
They expected that if principals were a primary cause of student success, schools that had the same principal for extended periods of time would see less variability, and schools that changed principals would see more variability. But neither was the case, the researchers found.
Instead, they found that other school factors unconnected to principals seemed to be driving these variations. Though there might be a correlation between student performance and principal effectiveness, there doesn’t appear to be a cause-and-effect relationship, Bartanen said.
The researchers concluded that these value-added measures produce “biased estimates of principal effects.”
The use of value-added measures in education has long been controversial. States rushed to integrate them into systems for evaluating teachers in the 2010s, but many have since backed off. Teachers’ unions in particular said the systems didn’t fairly evaluate their work.
Evaluating effectiveness through other metrics
Principals who spoke with Education Week said using student test scores as a metric in evaluating their effectiveness as a leader isn’t a bad idea, but other factors should also be considered.
“I see nothing wrong with looking at test scores,” said Larry Haynes, who has been a principal at Oak Mountain Middle School in Birmingham, Ala., for 18 years. But it’s also important to consider other outcomes, such as whether students are ready for the next grade level or whether they’re college and career ready, he said.
Harvey said principals should also be evaluated on the “compassion and the social-emotional wellbeing of our staff and our students.”
“You have to be the CEO of your campus, and when I say that I mean chief empathy officer,” said Harvey, who was the principal of Washington-Marion Magnet High School in Lake Charles, La., for four years. He’s now an administrative director of special education and alternative programs for the Calcasieu Parish school district.
“As a principal, you have to worry about creating a culture where everyone feels love, everyone feels the compassion, and everyone feels like they have the opportunity to be able to grow—as a student, as an individual, as a responsible adult that’ll be an asset for your community,” Harvey said.
Teachers, students, and parents should also have the opportunity to evaluate their principals and should play a big part in that, said Haynes, the 2022 Alabama Principal of the Year.
Bartanen hopes this research leads education policymakers and district leaders to reexamine “what we look for when we’re thinking about effective leaders” and the “perceived connection between principal performance and student outcomes.”
There’s more work to be done when it comes to figuring out how to measure a principal’s effectiveness—a task that is more challenging than measuring a teacher’s effectiveness, Bartanen said.
“Principals aren’t providing direct instruction to students in classrooms,” he said. “If there are impacts on student outcomes or student test scores, that’s mediated through their influence over school-level things that are directly related to their job,” such as hiring and retaining effective teachers, managing budgets, setting a strong vision for the school, and implementing teacher evaluation systems.
Bartanen said the research suggests there shouldn’t be a heavy reliance on student test scores to try to understand whether a principal is doing their job well, Bartanen said. When there isn’t such a hyper focus on test scores, principals will be able “to focus on other aspects of their role and other aspects of students’ lives,” he added.