The LA Times is beginning another series of articles about LAUSD, this series based on access they've had to LAUSD's longitudinal test data. Prior articles focused on money, with the Times creating an easily readable database listing all LAUSD employees' salaries. This time, they are focused on teaching.

The first article's intro says "A Times analysis, using data largely ignored by LAUSD, looks at which educators help students learn, and which hold them back."

To accomplish this,

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.

The article profiles a couple of strong and weak teachers, and apparently, more articles are forthcoming that will do more profiling. It seems that after analyzing the data, the authors went to the classrooms of those in the top decile and bottom decile for student improvement to view the teachers in action.

Miguel Aguilar at Broadous Elementary School is one of the strongest. "On average, his students started the year in the 34th percentile in math compared with all other district fifth-graders. They finished in the 61st."

That's an impressive improvement. I wish I understood enough details of the underlying scoring to know how this relates in standard deviations. Is improving a student one standard deviation when they one below the mean as difficult as improving a student one standard deviation when they are at the mean? Certainly it's not the same effort to move a students from 1 standard dev away from the mean to 2. What assumptions can be made about equal difficulty in movement of scores measured in percentile?

The article repeats what we all know as well: you must raise the bar.

"On visits to the classrooms of more than 50 elementary school teachers in Los Angeles, Times reporters found that the most effective instructors differed widely in style and personality. Perhaps not surprisingly, they shared a tendency to be strict, maintain high standards and encourage critical thinking.

But the surest sign of a teacher's effectiveness was the engagement of his or her students — something that often was obvious from the expressions on their faces."

The article goes on to argue that their analysis shows that excellence in teaching and weakness in teaching matter a great deal.

"Among the findings:

• Highly effective teachers routinely propel students from below grade level to advanced in a single year. There is a substantial gap at year's end between students whose teachers were in the top 10% in effectiveness and the bottom 10%. The fortunate students ranked 17 percentile points higher in English and 25 points higher in math."

The LAT is creating a database for release "in the coming months." I can't wait. I wonder if it will shed light on the value of mediocre teaching?

It's great to see this article. With luck, it will propel other journalists to perform similar studies. Perhaps some enterprising ed bloggers can FOI this information for their district, and perform the same analysis.