Joel Klein with a powerful Op Ed in the NY Post on this topic:

Now we face severe budget cuts that may force us to lay off 6,400 of the city's 80,000 teachers. And state law mandates -- and the union insists -- that these layoffs be done entirely on the basis of seniority. The most recent teachers hired are the first to get fired. No consideration of an individual teacher's merit or success with students, or the needs at that school.

It's painful to consider how many outstanding teachers our kids might lose simply because of their hiring dates. For example, most of our elementary-school teachers hired since the fall of 2007 will be lost.

Schools in districts with the most new teachers stand to suffer the largest losses. These include poor districts, whose challenges tend to lead to high turnover, and also districts that have grown in recent years and hired new teachers to keep up with enrollment.

The result: A poor area like the South Bronx is projected to lose 14 percent of its teachers, and the rapidly growing Upper East Side will lose 9 percent.

It doesn't have to be this way. State, city and union officials can together do two things to help us avoid the devastating impact of "last-in, first-out" layoffs.

…Second, the Legislature needs to truly prioritize the needs of our kids over any other consideration by mandating a system for teacher layoffs based on effectiveness, rather than time on the job.

As a first step, we would lay off the 1,600 teachers with "unsatisfactory" ratings and the 1,000 teachers who, by the time school starts again, will have been unable to find a job for a year. Beyond that, principals would make decisions based on three universally agreed-upon, clear criteria: teacher attendance, student progress and quality of teaching. Superintendents would review every decision to ensure they were supported by evidence. This is a common-sense approach that would end the absurdity of seniority-based layoff rules that spare no neighborhood in our city.

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