NEW YORK (AP) -- First came a hotly-debated decision by Cooper Union to start charging its students after being tuition-free for generations. Then came an investigation by the state attorney general into the school's management of its finances. Over the past year, Cooper Union's reputation as a world-class training ground for engineers, architects and artists has taken a back seat to headlines about the investigation, a lawsuit over the imposition of tuition and the future of its president. Some Cooper graduates and students hope all the turmoil results in more financial stability and maybe even a return to the tuition-free model that has been central to the school's unique, egalitarian character. "We know that students have had to refuse our offer because they couldn't afford it," said Mike Essl, a Cooper Union alumnus and faculty member who is a plaintiff in the lawsuit over the decision to charge tuition starting with this year's freshman class.