As Mayor Bill de Blasio readies the city for a prekindergarten expansion this fall, thousands of teachers will go through training at Bank Street College of Education to prepare as well, city officials said Friday.

Bank Street, a private teachers college in Manhattan, will offer the teaching institute next month to current and new full-day pre-K teachers and assistant teachers. More than 2,000 teachers have registered for the program, which is recommended but not mandatory. It will consist of three-day teacher institutes in Queens and Brooklyn.

The program confirms a tighter partnership between the city and Bank Street that Chancellor Carmen Fariña said she’d welcome when former deputy chancellor Shael Polakow-Suransky left the department to become Bank Street’s president in late January. Officials from Bank Street, long known for its early childhood education efforts, had said that the school was beginning talks with the department about teacher training that month.

The institute will consist of small group sessions where teachers will learn about working with families from different backgrounds, how to support English language learners, and students with disabilities, officials said.

“Class may be out for kids this summer, but it’s just starting for our pre-K teachers,” said Deputy Mayor Richard Buery.

Since the mayor took office in January, he has pushed to expand pre-K programs, leaving just eight months for the city to secure space and train personnel to reach its goal of 53,604 full-day pre-K seats available next fall, most of which are not new seats.