The study reviewed in this report examined the effects of Philadelphia's "Renaissance Schools Initiative" on students in K-8 schools after one year of implementation. Schools were selected for participation based on their School Performance Index (SPI) at the start of the 2010-11 school year. The SPI rates every school in Philadelphia from one to 10 (one being the highest achievement level and 10 being the lowest). The schools that were selected for the initiative had an SPI of 10. The study compared outcomes from 11 Renaissance Schools to those from 72 comparison schools that had an SPI rating of seven to ten. Study authors analyzed average student test scores in math and reading on the Pennsylvania System of School Assessment (PSSA) and average student attendance. The study reported that students in Renaissance Schools had significantly higher math achievement, reading achievement, and attendance rates than students in comparison schools. However, the What Works Clearinghouse (WWC) does not consider these results to be conclusive because the Renaissance Schools and comparison schools did not have equivalent average student achievement before implementation of the Initiative. Therefore, reported differences in average student outcomes between the schools might reflect these pre-program differences and not the effect of the "Renaissance Schools Initiative." The research described in this report does not meet WWC evidence standards. (Contains 2 endnotes.) [The following study is the focus of this "Review": "Philadelphia's Renaissance Schools Initiative: 18 Month Interim Report" (ED531671). For the "WWC Quick Review" of this report, "What Works Clearinghouse Quick Review: "Philadelphia's Renaissance Schools Initiative: 18 Month Interim Report," see ED530206.]