1959-60: Grafton and Joice leave for the Lime Rock Conference. Meservey and Thornton leave for the Iowa Westfork Conference. Hanlontown and Plymouth consolidate with Manly (Corn Bowl Conference) to form Defunct High Schools. Rock Falls is absorbed by Nora Springs (Corn Bowl Conference), which is renamed Nora Springs-Rock Falls. The new school competes in the Corn Bowl Conference. Swaledale consolidates with Rockwell (North Star Conference) to form Rockwell-Swaledale. The new school competes in the North Star Conference. Conference disbands.

1954-55: Joice, Hanlontown, Rock Falls, Plymouth, and Grafton of the North Six Conference; and Swaledale, Meservey, and Thornton form the Circle Lake Conference. Membership is 8.