Leslie maintains an active teaching career alongside her busy singing schedule. She has given Masterclasses at the American University of Sharjah in the United Arab Emirates, The Juilliard School in New York, Festival International Musica Classica Ribadeo, Spain, York University, Toronto and at numerous other festivals and institutions. For the past seven years, Leslie has been on the Voice Faculty at Sir Wilfrid Laurier University. Leslie regularly finds time to teach aspiring singers in her private home studio.