On a conference call with reporters to discuss the role of education in the president's budget, Secretary of Education Arne Duncan laid out four principles for performance pay for teachers. They were: 1. Rewarding teacher excellence 2. Getting the best and brightest into the toughest inner city and rural classrooms 3. Higher compensation for teachers in shortage areas, including math, science, and foreign languages 4. Support for alternative certification programs such as Teach for America, opening up teaching to non-education majors Points two through four here are not particularly controversial. The rub, of course, is the details involved with point one -- how exactly do we determine "teacher excellence?" And most importantly, especially in the minds of teachers, what role do student test scores play in that determination? Duncan wouldn't say, though he did tell a Colorado reporter on the call that Denver's celebrated Pro-Comp system, which includes student achievement as just one metric to assess teacher excellence, is not the only model he supports. Duncan noted that 36 districts across the country are doing "interesting things around compensation," and that he hopes federal dollars will increase that number to 150. --Dana Goldstein