Dennis-Yarmouth Regional High School is a suburban public high school (grades 8-12) in Yarmouth, Massachusetts. It opened in 1957 and was expanded and renovated in 1979, and again in 2006. The school serves the communities of Yarmouth and Dennis, and has an enrollment of approximately 1,000 students. Dennis-Yarmouth, or known more commonly to the locals as "D-Y", is the second largest high school (in terms of student population) on Cape Cod, behind only Barnstable High School. It is in South Yarmouth, just south of the Mid Cape Highway.