An appeals court Friday upheld a controversial law more closely tying teachers’ pay to how well students do on tests, ruling that the Legislature didn’t give too much leeway to the Florida Department of Education to decide how to implement the measure.

In a 10-3 vote with two judges recusing themselves, the First District Court of Appeal rejected a challenge, backed by the state’s largest teachers union, to the “Student Success Act.” The court’s decision focused on whether part of the law was specific enough on how to set up the standards deciding which teachers received each of the law’s four ratings.