Teach For America, which trains high-achieving college graduates to enter troubled public school classrooms, is getting a $3 million donation to add 510 teachers in New Orleans, officials announced Wednesday morning.

The contribution is part of a $20 million gift from the Walton Family Foundation, which aids a variety of programs aimed at improving public education.

The money will support the recruitment, training and professional development of nearly 4,000 first and second-year teachers in nine cities, including New Orleans.

TFA already has a large presence in New Orleans, in part because of the spread of charter schools and other steps aimed at improving the city’s long-suffering public school system.