Dennis served as head wrestling coach at Warrenton high school for 26 years. During his tenure with the Warriors, his teams won five district titles and finished in the top 10 at the State Tournament 17 times. He coached 59 district champions, 55 state placer‘s, and 17 individual state champions. At least seven of his wrestlers went on to compete at the college level. Dennis was named Oregon 2A wrestling coach of the year in 1976. In 2010 he was also inducted into the Warrenton Hall of Fame as coach of the 1990 wrestling team. He retired from coaching and teaching in 2004 but continued to serve the Warrenton community as a member of the school board and the founder and director of the PEOPLE scholarship program (providing scholarships for Warrenton High School graduates). As of 2010, the program awarded 11 full tuition scholarship to students attending Clatsop community college. The students have maintain an average B+ GPA and contributed hundreds of hours of community service in Warrenton schools. The program was on track to reach $100,000 in 2010.