Gaston Junior/Senior High SchoolGaston Junior/Senior High School is a public high school in Gaston, Oregon, United States.WWW gaston.k12.or.us/Jr-Sr%20...AcademicsIn 2008, 78% of the high school's seniors received their high school diploma. Of 45 students, 35 graduated, five dropped out, and five were still in high school the following year.