Linking teacher pay to performance -- not just to seniority and post-college credits -- was the center of education reform in the 2010s, writes Martin R. West in Education Next. The Obama administration pushed most of the states to adopt new teacher evaluation systems that included some measure of students' progress.
But evaluating teachers proved to be very difficult: Very few teachers received low ratings. In most districts, there was no effect on achievement.
A flop? Not necessarily, writes West. When teacher evaluation and pay reforms are implemented well, students learn more. In Washington, D.C., for example, the IMPACT system produced gains, as reported in A Lasting Impact in 2017. "Strong teachers improved their performance, ineffective teachers left the district, and student performance rose."
A 2011 Wisconsin law, Act 10, “allowed school districts to set pay more flexibly and without unions’ consent," writes Yale economist Barbara Biasi in Education Next. About half of districts used the flexibility to detach pay from seniority and credentials, while the other half maintained the status quo.
In flexible-pay districts, "teachers who were more effective in raising students’ test scores started to earn more than their peers," Biasi found. These "districts saw more weak teachers depart and experienced an influx of effective teachers, many of them poached from districts that stuck with seniority-based pay." Teacher performance and student achievement rose.
Districts with lower-income students were less likely to adopt flexible pay, and lost effective teachers. In addition, "a gender pay-gap emerged, as women proved less likely than male teachers to negotiate with male principals for higher salaries."