The Los Angeles Times a few years ago published a public database with Teacher Ratings based on Value Added Analysis. Value-added is a statistical approach that estimates a teacher's effectiveness at raising student performance on standardized tests. In essence, it projects a child's future performance by using past scores -- in this case, on math and English tests. That projection is then compared to the student's actual results. The difference is the "value" that the teacher added or subtracted. Comparing each student to him or herself in the past largely controls for differences in students' backgrounds.
Mr R's Teacher Ratings compared to other same school faculty members shown below:
Mr R's LAUSD Teacher Rating
The next set of graphs show Mr R's individual "value-added" rating based on his own students' progress on the California Standards Tests in math and English. The Times’ analysis used all valid student scores available for Mr R from the 2002-03 through 2008-09 academic years. The value-added scores reflect a Mr R's effectiveness at raising standardized test scores and, as such, capture only one aspect of a teacher's work. Mr R's Individual Teacher Rating on LA Times shown below: