A new report from Tulane University’s Education Research Alliance of New Orleans says students are hurt when schools are measured solely on test scores, in part because it encourages schools to pick the brightest and push out low achievers.

ERA Director Doug Harris and Senior Research Fellow Lihan Liu boiled school accountability down to one sentence: “What gets measured gets done.”

Harris and Liu explored school accountability by adding other metrics, such as student improvement and college admissions, to see how schools’ ratings — from A to F — would shift.

“Ultimately we should have performance measures that reflect what we care about,” Harris said Monday. “So it’s really up to the school board and the state to decide what we care about.”

The state Department of Education sets its own formula for its official letter grades, which until this year were almost entirely based on standardized tests. This year, 25 percent of elementary school letter grades will be based on growth. Failing schools can be taken over by the state.

But the Orleans Parish School Board can establish its own standards for charter renewals. Since Hurricane Katrina, nearly every school in New Orleans has become a charter school.

Those schools are funded by taxpayers, but they’re free to set their own curriculum as long as they meet certain goals.

Right now, the school board bases its charter renewals on the state’s ratings. Schools aren’t graded for the first two years after they’re taken over by a new charter operator. To get the first renewal, a school must have a D or better. For later ones, it must be a C or better.

“If we’re going to close and take over schools based on their performance measures, then those become really, really important,” Harris said.

The school board’s accountability committee will discuss the district’s accountability framework Tuesday, with the full board expected to vote Thursday. Harris hopes the report will foster dialogue about how schools should be evaluated.

Its decision will carry more weight this year, as all Recovery School District charter schools will return to the parish school system this summer.

How do we hold schools accountable?

In a city where test scores can determine whether a school stays open, Harris and Liu wrote that how schools are measured is particularly important.

They compared different accountability methods, which have long been a topic of public debate.

Some argue schools should be measured solely by standardized test scores, with the expectation that every student should be be proficient in certain subjects. Others argue this approach penalizes schools with struggling students and encourages schools to kick them out.

When the federal government transitioned from the No Child Left Behind Act to the Every Student Succeeds Act, which dropped the 100 percent proficiency goal, states were given more freedom in how to hold schools accountable.

Holding schools accountable for absolute outcomes creates what Harris described in the report as a “starting-gate inequality,” rewarding schools that serve advantaged students.

One solution, Harris wrote, is to factor other things into school evaluations. He made the case for a measure called “value-added,” in which a school is measured by students’ progress over time or progress relative to expectations.

“Value-added rewards schools for helping students no matter where they start,” he and Liu wrote.

At the high school level, they suggested combining test scores with graduation rates or college enrollment. Harris said college admission is an especially good indicator, “given how strongly that is related to students’ long-term success.”

The two noted that adding these factors could change school letter grades. For instance, a failing school may get a better grade from the state if its students’ performance improved and improvement were taken into account.

“This is an opportunity for the city to move in a direction that is more sophisticated and more accurate, that in the long term will end up improving the outcomes that we care about in the city,” Harris said.

Marta Jewson covers education in New Orleans for The Lens. She began her reporting career covering charter schools for The Lens and helped found the hyperlocal news site Mid-City Messenger. Jewson returned...