Barbara Martinez in the WSJ with an article about reason #3,423 that the teachers union contracts screws kids: in this case, NYC principals can't hire "fantastic" teachers because they are being forced to hire from the excess teacher pool, which is mostly filled with the dregs of the 80,000 teachers in NYC:

Amid all the recent talk of possible teacher layoffs, the city's Department of Education is actually on a hiring spree, but hiring restrictions are making it difficult for principals to fill open jobs.

"We found a fantastic science teacher," said Anna Hall, principal at the Bronx Academy of Letters, but she said she was prevented from taking on the applicant.

Since May 2009, the department has restricted schools to hiring from an existing pool of teachers, except for certain areas, such as teachers who are trained in special education, speech and certain bilingual subjects. New schools can also hire external candidates for up to 40% of their vacancies in the first three years of their existence.

While most of Bronx Academy's teacher openings are usually filled by this time of year, Ms. Hall's four postings are still open, and "it's not for lack of looking," she said.

----------------------