... programs such as Teach for America and the city's Teaching Fellows program have made the distribution of high-achieving teachers more equitable across New York City and might have helped narrow the gap in students' test scores, a recent study concludes. ... And Jim Wyckoff, a University of Virginia professor who was one of the authors of the study, told me his analysis suggested that if schools only 'hired teachers who looked like the best group,' or the very best college graduates, student achievement could rise even more.