Bill Gates Supports Grading Teachers

Incentives matter

(CNN) -- Today I released my annual letter. Each year, I reflect on what I learned in the last year through our travels and work with the foundation and how that will shape my thinking over the coming months. This year, my letter focuses on how important it is to set clear goals and measure progress in order to accomplish the foundation's priorities, both here at home and around the world.

Setting a clear goal lets you know what you're driving at: Picking the right interventions that will have the most impact on that final goal, using that information to understand what's working and what's not, and adapting your strategy as necessary. One of the clearest examples of the power of measurement was the work of our partners to support great teachers.