Please answer the following question: Old Mill School (Mill Valley California) -  Old Mill School is one of 5 public elementary schools in Mill Valley California along with Park Tamalpais Valley Edna Maguire and Strawberry Point Schools. The main building built in 1921 is the oldest existing public elementary school building in Mill Valley. At the beginning of the 2006 school year there were 290 students at Old Mill in kindergarten through 5th grades and 14 grade-level teachers assisted by subject-specific teachers and teacher's aides. Given a choice of categories company, educational institution, artist, athlete, office holder, mean of transportation, building, natural place, village, animal, plant, album, film or written work, the text refers to which one?
Answer:
Educational Institution