ST. PAUL — The Minnesota Senate passed a bill Monday that would let schools lay off teachers based on their performance in the classroom rather than by seniority alone.

The bill passed by a 36-26 vote would let schools make layoffs based on evaluations that consider how well a teacher’s students perform. The state currently requires school districts to consider only teacher seniority in deciding layoffs, unless individual districts negotiate their own arrangements to consider other factors.

The bill’s lead sponsor, Sen. Pam Wolf, R-Spring Lake Park, said the legislation would allow schools to keep the most effective teachers.

“More matters than just when you sign the contract,” said Wolf, who teaches a range of grades at Pines School at the Anoka County Juvenile Center.

Several Democrats opposed the bill. They said a statewide teacher evaluation system now in the works needs more time to develop before layoff policies are changed. The new system would base about one-third of a teacher evaluation on student test results.