Since 2011, when Republicans controlled the Legislature and the governor’s office, 40% of a public school teacher’s job performance evaluation has been based on their students’ performance on standardized tests.

Proponents of the law mandating such evaluations say it ensures administrators grade teachers on how well they perform their primary task: making sure students learn. Opponents say standardized tests do not fully measure student achievement because some students learn well but test poorly and that the law creates an unfair burden on teachers who sometimes struggle to bring up to par kids whose home-life struggles make it difficult for them to perform well academically.

Now, Democrats control the Legislature and the governor’s office, and they’ve amended that law to say that, starting next school year, no more than 20% of a teacher’s evaluation can be based on standardized test scores. The law leaves it up to administrators and teachers union to decide at the negotiating table exactly what percentage of the evaluation will be based on test scores.

That is a monumental shift. In a district with poor test scores — often the district with the largest share of students who come from low-income families — dropping from 40% to 20% (or lower) could mean the difference between many teachers keeping or losing their jobs.

Now that Democratic Gov. Gretchen Whitmer has signed the new law, school administrators and teachers unions will probably head to the bargaining table this winter or spring to iron out the exact percentage.

Residents — both parents of the schoolchildren taught by the district and taxpayers who pay the teachers’ salaries — need to talk to their local school boards about what kind of percentage they’d like to see.

Should districts settle on the maximum 20% so test scores mean more of a difference between a good or a poor job performance rating? Or should they go lower and instead base more of the evaluation on other measurements, such as administrator observations of how well the teacher teaches in the classroom?

School boards should take residents’ wishes into account when they head to the negotiating table with the teachers union.