Another recent paper finding similar results:

http://www.people.fas.harvard.edu/~dobbie/research/ExamSchools_July2011.pdf

Exam High Schools and Academic Achievement: Evidence from New York City
Will Dobbie, Roland G. Fryer, Jr.
NBER Working Paper No. 17286
Issued in August 2011
Abstract: Publicly funded exam schools educate many of the world's most talented students. These schools typically contain higher achieving peers, more rigorous instruction, and additional resources compared to regular public schools. This paper uses a sharp discontinuity in the admissions process at three prominent exam schools in New York City to provide the first causal estimate of the impact of attending an exam school in the United States on longer term academic outcomes. Attending an exam school increases the rigor of high school courses taken and the probability that a student graduates with an advanced high school degree. Surprisingly, however, attending an exam school has little impact on Scholastic Aptitude Test scores, college enrollment, or college graduation -- casting doubt on their ultimate long term impact.


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