The Times obtained seven years of math and English test scores from the Los Angeles Unified School District and used the information to estimate the effectiveness of L.A. teachers — something the district could do but has not.
The Times used a statistical approach known as value-added analysis,
which rates teachers based on their students' progress on standardized
tests from year to year. Each student's performance is compared with
his or her own in past years, which largely controls for outside
influences often blamed for academic failure: poverty, prior learning
and other factors.
Though controversial among teachers and others, the method has been
increasingly embraced by education leaders and policymakers across the
country, including the Obama administration.
In coming months, The Times will publish a series of articles and a
database analyzing individual teachers' effectiveness in the nation's
second-largest school district — the first time, experts say, such
information has been made public anywhere in the country.
The series examines the performance of more than 6,000 third- through
fifth-grade teachers for whom reliable data were available.
Read Jason Felch and Jason Song's full investigation here. In the video above, Felch discusses the series.
