Dewy coached at Purdue for 20 years before retiring in 1994. She holds the record for career wins at Purdue, posting a 469-256 mark. In her tenure at the school, Purdue won four Big Ten Championships and made nine postseason appearances. Under Dewey's guidance, six Boilermakers were named AVCA All-America and 39 players received All-Big Ten honors. Dewey was named Big-10 Coach of the Year on three occasions.
Dewey was a true pioneer of collegiate volleyball as Purdue was one of the first schools in the country to emphasize the sport. With Dewey's leadership Purdue changed the way volleyball was being supported and viewed on the college campuses. Thus, Purdue became a model program for other schools to follow in the 1980s. She had a tremendous influence in the growth of the sport and on the coaching profession.
Dewey was also a member of the first NCAA Volleyball Championship Selection Committee in 1981 when the NCAA opened championships to women's sports. She was an active member of the AVCA All-America Committee. Dewey was quite a player in her day as well. She was a member of the 1976 United States National Team and played with E Pluribus Unum, winning national championships in 1972 and 1973.