WASHINGTON, DC (AP).- The Kennedy Center for the Performing Arts announced the largest private donation in its history Monday — a $22.5 million gift from Dick and Betsy DeVos to endow a management training program for arts leaders. Arts organizations have been struggling or even closing their doors in the recession and need expert leadership to survive, Betsy DeVos said. The gift is among the largest ever by the Michigan couple. “We spend millions and billions of dollars training the most talented artists in the world, and yet we have invested very little historically in actually helping train and prepare their leadership, those who manage and employ them,” she said. The gift will help fund two-year arts management training programs across the country. The center already has trained leaders from more than 400 small to mid-sized groups in New York,