As a loan recipient, Yonnie first connected with LDHL while seeking financial aid for college after graduating from Manheim Central High School in 1961. She took a gap year to earn money, then applied to LDHL (formerly Citizens’ Scholarship Foundation of Lancaster County), receiving about $1,600 for her four years at Bridgewater College. Yonnie earned a B.S. in 1966 and repaid her loan by 1968, so future students could benefit as she did.

During her tenure at Elizabethtown College, Yonnie became one of the winningest coaches in U.S. sports. Under her leadership, the women’s basketball team secured two NCAA championships, the women’s field hockey team reached the Final Four, and the women’s tennis program saw both a national champion singles player and a national champion doubles team.

In 2024, Yonnie established the Robert Kauffman Memorial Legacy Loan in memory of her brother, Bob, to recognize a period when they shared in financing each other’s educational expenses. During Yonnie’s senior year of high school, Bob noted that attending college simultaneously would not be financially feasible for both of them. He suggested that Yonnie work full-time for a year to support his final year as a full-time student; in return, he agreed to support Yonnie throughout her four years in college.