PITTSBURGH – While the teachers unions gave it their best shot, they haven’t been able to convince the public that all teachers are equally skilled and deserve a long, interrupted career in education.

Too many studies have clearly demonstrated the difference a skilled teacher can make to children, and the damage that an unskilled teacher can cause.

The presence of quality teachers is even more important in urban schools, where parental support may not be as strong, and the ability of teachers to capture the attention of students may be the only hope for some of those kids.

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Officials in the Pittsburgh school district came to this realization about five years ago and implemented the Research-Based Inclusive System of Evaluation (RISE) for teachers. The new system replaced the horrible old “satisfactory or unsatisfactory” teacher evaluation model, which is still largely employed across Pennsylvania.

Mark DeSantis, an adjunct professor at Carnegie-Mellon University, recently published a guest editorial in the Pittsburgh Tribune-Review, acknowledging the importance of the RISE system and bemoaning the fact that it could soon fall victim to union policies and political shenanigans.

“Can you imagine asking a friend for a pediatrician recommendation and getting a ‘satisfactory’ response?” he wrote. “Satisfactory isn’t good enough in the teaching profession, and unsatisfactory is not acceptable.”

DeSantis noted that the RISE system allows administrators to group teachers into four different categories that more accurately identify their skills.

The top group (15 percent of teachers) are terrific, while many in the middle are rated “proficient” or “needs improvement.” The bottom 10 percent are rated as poor, and are, in the words of DeSantis, “failing our city’s students.”

“These teachers are in need of serious developmental remediation, or, in some cases, termination,” he wrote.

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Without the tools to differentiate effective from non-effective teachers, there would be no way to seriously improve schools, according to DeSantis.

“A crude ‘satisfactory’ or ‘unsatisfactory’ never would have identified either the excellent teachers or the failing ones, let along discerned the proficient ones from those needing improvement,” he wrote. “Many factors affect student performance, but failing to use the readily-available and proven assessment tools now common in a host of high-skill professions like teaching means failing to acknowledge excellence and embracing mediocrity while contributing to still further dismal performance.”

Unfortunately the RISE program may be in trouble in Pittsburgh for a number of reasons, according to DeSantis. The first is a shaky financial foundation that could lead to layoffs in a few shorts years. While the district has an updated teacher evaluation system, it’s still stuck with the outdated “last in, first out” layoff police dictated by the teacher union contract.

That could make it likely that some of the best teachers would be laid off, regardless of their skill, just because they lack seniority.

Meanwhile, the Pittsburgh Federation of Teachers is pushing for an alteration to the RISE system that would eliminate the component making it possible to identify the lesser teachers, according to DeSantis.

The union is also creating problems by opposing Superintendent Linda Lane’s effort to secure the right to make layoff decisions to protect top teachers, or to make sure skilled teachers remain in the city’s most hard-to-staff schools.

“If we are not able to separate the excellent, good and trying-hard teachers from the failing teachers, then any evaluation system loses its purpose and meaning and we return to mediocrity or worse,” DeSantis wrote.

“Every student in our city deserves the highest quality teaching possible and we must be willing to do everything to provide it.”