When school starts next fall, Teach for America will send an unprecedented number of college graduates to teach in poor communities across the country — but not as many as the group would like.

Teach for America this year chose 4,100 recruits from more than 35,000 applications. While the group has never accepted every applicant, this was the first time it had to turn down people who met all its rigorous criteria.

“For the last nine years, really the only constraint on our growth has been recruits, just finding enough people who we really believe are ready for this,” said Wendy Kopp, the group’s founder and chief executive.

“This is the first year when we’ve had to turn away people who would have met our admission bar in any previous year,” Kopp said.

The constraint is the economy. Tighter budgets have forced some school districts to cut back on hiring, though overall 500 more spots for Teach for America are available this year. Also, those who give to nonprofits like Teach for America are either holding the line or cutting back on their charitable giving, which pays for training and professional development for the recruits.

Despite the belt-tightening, some communities expect an influx of new teachers from the program, especially in rural areas. South Louisiana and the Mississippi Delta will have more than double the number of recruits this year.

In Mississippi, state schools chief Hank Bounds asked Teach for America for at least 200 new teachers. Bounds believes the program’s high-achieving graduates will play an important role in turning around his state’s struggling schools.

Children suffer from poverty in Mississippi at a greater rate than the national average. And fourth-graders there trail the nation and region in reading and math, though they have made gains since 2003, according to the Southern Regional Education Board.

The South holds particular interest for some recruits. Yale graduate David DeAngelis asked specifically for assignment to the Delta, and he spent the past year teaching music in tiny Marianna, Ark., near the west bank of the Mississippi.

“You become part of the community almost immediately, part of the lives of students, of students’ families,” DeAngelis said. “It’s a very rich and powerful experience, from the very beginning.”

Urban schools are also asking for more. In Baltimore, school officials asked Teach for America to send 150 new teachers, twice the number of last year’s recruits. However, Teach for America still needs to raise $500,000 to pay for the increase.

Interest in becoming a teacher has soared amid the recession, especially in programs that get people quickly into the classroom.

Teach for America, for example, provides five weeks of intensive summer training before the school year begins and requires a two-year commitment from its recruits.

Other programs help people switch from other careers into teaching. One of the largest is the New Teacher Project, which has seen a surge in applications like that of Teach for America.

Teach for America has endured its share of criticism. Recruits are less likely to stay in the classroom than those who come from traditional colleges of education, although opponents point out that the low-income schools where they work have much higher turnover anyway.

Still, after their two-year commitment, two-thirds of Teach for America alumni are still working in education, according to the organization. About one-third are working as classroom teachers, and others are in administrative jobs such as principal or school superintendent.

Opponents have also questioned the effectiveness of TFA teachers, although a growing body of research suggests they are as effective or more effective than teachers who followed more traditional routes to the classroom.

On the Net:

Teach for America: http://www.teachforamerica.org/