Sunnyside is on U.S. Highway 385 fifteen miles south of Dimmitt in Castro County. It was founded in 1912 when two rural schools, Axtell and Roush (both named after area settlers), were merged at a central location. The site originally was included in the XIT Ranch lands and later in the William E. Halsell survey. Another area resident, Jeff Gilbreath, named the school Sunnyside because of the climate and also because he had lived near Sunnyside, Tennessee. The Sunnyside Baptist Church was organized in this school in 1921. Four years later a new brick facility replaced the original building, and a church was constructed on the other side of the road. A store was built in 1930. Lack of water was a frequent problem, and Sunnyside suffered badly during the Dust Bowl. In 1935 R. E. Cade drilled the area's first deep irrigation well two miles east of Sunnyside. Other farmers soon followed suit; by 1971 at least one deep well was to be found on every area farm. In 1941 the Rural Electrification Administration assisted in bringing electric power to the area. The Sunnyside school ceased operations in 1942, and in 1945 the Sunnyside School District was partitioned among Dimmitt, Springlake, and Hart. Nevertheless, the community lived on. In 1951 a cotton gin was built, and El Paso Natural Gas established a booster plant and a ten-family housing unit just south of the county line. On April 12, 1960, a tornado demolished several buildings, killed three, and injured sixty. However, the residents, with help from neighboring towns and churches, soon built back. The Lions Club turned a store building into a community center in 1972 and in 1979 provided the community with fire-fighting equipment. Since then the club has hosted an annual Fourth of July celebration, complete with fireworks. With a new church and a gin and five other businesses, Sunnyside reported a population of 106 in 1980 and 1990. The population dropped to eighty by 2000.