Right now, almost half of all Buffalo students don’t graduate from high school. Half the students. It’s hard to imagine how Buffalo can survive, much less revive, when nearly 50 percent of its students don’t even earn a high school diploma.

And when Buffalo students do go to college, far too many of them need remedial work – they end up paying for high school courses in college. And students taking those remedial courses are far less likely to finish their degrees.

Something has to change in Buffalo.

The bottom line is that we need to make a bold, systemic change to help Buffalo students – indeed, all of New York’s students – graduate high school ready for college and careers.

In February, Gov. Andrew M. Cuomo stood with state Education Commissioner John B. King Jr. and the head of the state teachers unions to announce agreement on a new evaluation system for teachers and principals. The new law was a groundbreaking agreement that laid the foundation for a fair, responsible process to provide educators with constructive evaluations that can strengthen teaching and learning.

Nine months later, more than 600 school districts around the state have submitted evaluation plans, and King has approved hundreds of them. Unfortunately, Buffalo still hasn’t submitted an approvable plan for review.

Buffalo stands to lose tens of millions of dollars if it doesn’t have an approved plan in place by Jan. 17. This is not about a “gotcha” system to get rid of teachers. This is about giving teachers and principals the tools they need to strengthen their skills and improve their instruction. And it’s about giving all Buffalo students a chance to succeed in college and careers.

Research and common sense tell us the best way to improve student performance is to make sure that every child is in a class headed by a great teacher and that every school is run by a great principal.

Common sense tells us something else: Just like the rest of us, teachers and principals need objective feedback to get better at their jobs. An effective evaluation plan lets educators receive professional development tailored to their needs, and gives top practitioners the opportunity to serve as mentors for their colleagues.

That’s why the state Board of Regents included implementation of strong evaluation as one of the key pillars of its education-reform agenda.

Some of the debate has been over the use of student test scores to measure teacher performance. The complaint is that test scores don’t give full measure of a teacher’s performance. That’s true: Student test scores are only one measure of an effective evaluation system. But they are an essential measure.

The new law limits the use of state student-growth scores to 20 percent of evaluations, with another 20 percent of the score derived from locally negotiated objective measures. The remaining 60 percent is negotiated between the district and the local unions, and there are a number of options (e.g., supervisor observation, peer and student review, professional development) that can be adopted.

The student-growth scores provided by the state for teacher evaluations are adjusted for factors such as students who are English language learners, students with disabilities and students living in poverty. When used right, growth data from student assessments provide an objective measurement of student achievement, and by extension, teacher performance.

We should never judge an educator solely by test scores, but we shouldn’t completely disregard student performance and growth either.

An effective evaluation plan – built on objective measures such as student growth scores on standardized testing and subjective measures such as classroom observations – that provides constructive feedback and appropriate professional development is a vital piece of that change.

Change is never easy. But it is necessary. Hundreds of districts and local unions large and small across the state have found a way to get this done. It’s frustrating that Buffalo, the state’s second largest school district, can’t find a way to reach some common ground. The Buffalo School Board and the unions should do everything possible to expedite the submission of an approvable plan. Further delay only increases the damage done to our children’s – and Buffalo’s – future.

We would never accept this kind of result from our students.

Merryl H. Tisch is chancellor and Robert M. Bennett is chancellor emeritus of the New York State Board of Regents.