In 1840, the high school moved into a new building located between Kirk Street and Anne Street along the Merrimack Canal. Over the next 100 years, the school campus expanded. The oldest extant building replaced the 1840s building in 1893. In 1922, a large new building was built along Kirk Street and in the 1980s another building was built on the opposite side of the Merrimack Canal with connecting walkways over the canal. There are now three major buildings with one limited to the Freshman Academy. Current enrollment is over 3000 students.