John Franklin Lavelle, of Lancaster, died peacefully on January 20, 2019 at Hospice & Community Care in Mount Joy. He would have been 85 this January. He was born in Minneapolis, MN to the late John Joseph and Evelyn Cartwright Lavelle. He was the loving husband of Margaret Ann Lavelle, sharing 61 years of marriage. John was a scholar, a teacher, a mathematician, a father, grandfather and great grandfather. He received his doctorate in Mathematics with a specialty in algebraic number theory from Penn State University. He pursued his career as a Professor of Math and Computer Science at Millersville University, retiring after 35 years in 1994. He lived and taught for a short period in England as well. John was an avid golfer, bridge and chess player, often going to tournaments. He also enjoyed traveling with his wife to destinations such as Russia and China. John was a member of St. Philip The Apostle Catholic Church. Surviving, in addition to his wife, is a daughter, Julie A. married to Jerry M. Miller, and a son, Gregory H. married to Athena C. Lavelle. He has three grandchildren: Kurtis M. Miller married to Izabela, Kristin Miller Biagio married to Nicholas Biagio, and Madeline G. Lavelle, and 2 great grandchildren Gabriel Miller and Brynna Biagio. He was preceded in death by his son, John Arthur Lavelle and his brother, George Cartwright Lavelle. Friends will be received at St. Philip The Apostle Catholic Church, 2111 Millersville Pike, Lancaster, PA on Friday, January 25, 2019 from 10-11AM, with the Mass to follow at 11AM. Interment in Millersville Mennonite Cemetery. In lieu of flowers, please make contributions in John's memory to Hospice & Community Care, 685 Good Drive, Box 4125, Lancaster, PA 17604-4125.