More than 500 extra teachers rated "unsatisfactory" this year

City principals rated more teachers unsatisfactory this year than they have since at least 2005, suggesting that the Bloomberg administration’s efforts to escort more struggling teachers out of the system may be bearing some fruit.

Principals gave the scarlet-letter rating to 1,554 teachers this year, up from 981 in the 2005-2006 school year, data provided by the city Department of Education show. Both the number and percentage of teachers rated unsatisfactory rose during that period, and the rise occurred for both tenured and non-tenured teachers, city figures show.

Even with the rise, the percentage of teachers rated unsatisfactory remains low. About 2% of teachers, both tenured and without tenure, received what teachers call “U” ratings this year.

Ann Forte, a schools spokeswoman, sent us the figures this afternoon.

The rise follows a concerted effort by school officials to make it easier for principals to terminate poorly performing teachers, including a new group of lawyers assigned to targeting struggling teachers, called the Teacher Performance Unit. Rating a teacher unsatisfactory is often the first step toward removing him from the school system.

A recent bout of research argues that poor teaching is partly to blame for poorly performing schools, and a report by The New Teacher Project singled out poor teacher evaluation systems as part of the problem. The report specifically criticized evaluation systems that offer principals binary choices, either satisfactory or unsatisfactory, rather than encouraging more nuanced feedback. U.S. Education Secretary Arne Duncan endorsed the report, and his staff has urged school districts to improve their teacher evaluation systems.

New York City teachers receive either an “S” or “U” rating from their principals once a year.

Randi Weingarten, the president of the city teachers union and of the national American Federation of Teachers, has criticized the city’s efforts to target struggling teachers, decrying the Teacher Performance Unit as a “gotcha squad.”

Below is a chart showing the raw numbers of teachers receiving “U” ratings, and we’ve uploaded data from last year here.