Lewis & Clark League
The 3A Lewis & Clark League was formed in 2006. It originally had these schools as members: Catlin Gabel, Clatskanie, Neah-Kah-Nie, Oregon Episcopal School, Portland Adventist Academy, Rainier, Riverdale, Vernonia, and Warrenton. In 2009 Riverdale dropped out. The next year, Neah-Kah-Nie and Vernonia were moved to the 2A Northwest League and Corbett, De LaSalle North Catholic, and Valley Catholic joined the League. In 2014, Valley Catholic and Corbett moved up to the 4A Cowapa League and Portland Christian joined the league and Riverdale rejoined the Lewis & Clark League.
Currently, the 3A Lewis & Clark League is made up of the following schools: Catlin Gabel, Clatskanie, De La Salle North Catholic, Oregon Episcopal School, Portland Adventist Academy, Portland Christian, Rainier, Riverdale, and Warrenton.