When David and Libby Savner donated $1 million to Northwestern University School of Law, professor Emerson Tiller knew immediately how he wanted to see the money used — a flipped classroom. It’s an education model where students watch filmed lectures at home prior to class and spend class time reviewing the lectures and doing their homework. Rather than spending class time listening to teachers talk, students have the benefit of absorbing lectures at their own pace. “This is typically done with …