At Binghamton, Calculus 1 is taught to over 1000 students each fall in sections of about 30-40 students, with graduate student instructors teaching most sections. Despite having small classrooms instead of lecture halls, the satisfaction and performance of students has historically been poor. We had hoped to improve student success by changing how we teach and not by lowering our standards. In the fall of 2013, the Binghamton University Department of Mathematical Sciences undertook an experiment in flipped teaching with Calculus 1 in which we compared a flipped model to our traditional lecture model. Overall, our quantitative analysis found moderate benefits to flipping over traditional methods for all groups studied. Informally, while student opinion varied, instructors largely were quite positive, finding that their students were more engaged and that instructors were able to give students more individualized attention.