McKinley Elementary School began in 1915 as a series of portable buildings with just three teachers. In 1921, both the elementary and the junior high students were relocated to the McKinley School Center, the current junior high. Overcrowded conditions at the center forced some of the elementary students to return to the portables and eventually initiated the construction of the McKinley Elementary School as it stands today.
Construction of the 26-room school began in March of 1949. The total cost of the school was $475,000. McKinley Elementary School opened its doors in September of 1950 with an overflow enrollment of 620 pupils. On October 26, 1950, McKinley Elementary School was dedicated to the children of Kenosha.
The school was named in honor of William McKinley, the twenty-fifth President of the United States.