America's schoolteachers are some of the most brilliant, driven and highly skilled people working today—exactly the kind of people we want shaping young minds. But they are stuck in a system that doesn't treat them like professionals.

In most workplaces, there is an implicit bargain: Employees get the support they need to excel at their jobs, and employers build a system to evaluate their performance. The evaluations yield information that employees use to improve—and that...