History of Lanark Schools
In the early part of 1862, the sitting room of Richard Thompson, located at 217 E Locust St., was said to have been the first to serve as a school. In 1867, Alexander Smith, was hired to construct a school that was a three story brick with a mansard roof. School opened in 1867. It 1875, an “official” high school curriculum was adopted, so that the class of 1876 was considered the first graduating class of Lanark High School. The citizens 
on the north side of town were concerned about their children crossing the busy railroad tracks so they petitioned for a grade school of their own.
In 1883, the North Side School was built at the north end of Boyd Street between 117 and 207 W Leland Street. In 1894, it was closed and the children again attended the south side school. The North Side School building was periodically used as a gymnasium until it was torn down about 1915.
The Lanark High School building was discovered ablaze at three o’clock Saturday morning, November 25, 1893. In January 1884, the Board of Education reported progress for a new building on the sites where the old building had burned. The building was 91’ by 61’ two story, but with a semi-exposed basement and dormer attic surely enough to say, three stories.
In 1911-12, a large addition was put on the east side due to increased enrollment. The new gymnasium was erected in 1928.
These are excerpts from the book “Sesquicentennial Lanark IL 1861-2011”