In 1976, one of its original members, Mechanic Arts, was closed, and in a span of two years from 1977 to 1978, Monroe, Washington, and Murray high schools would do the same.

Most of the students from Washington and Murray were incorporated into Como Park Senior High School.

In 1977, the conference added four private schools from the Saint Paul area: Cretin, Derham Hall, Hill-Murray and St. Thomas Academy.

Coaches were concerned that the private schools were winning a disproportionate amount of conference titles and had several unfair advantages.

Hill-Murray was accepted into the North Suburban division while Saint Thomas Academy was rejected for not meeting the criteria of the original twenty three schools.

[8] A month after Hill-Murray and St. Thomas were dropped the Minnesota State Legislature held a legislative task force to discuss the Minnesota State High School League's role in placing school's in athletic conferences.

[11][12] Eventually in the Spring of 1988, the Minnesota State High School league placed Saint Thomas Academy in the Saint Paul Suburban Conference, a member of the Twin Cities Federation[8][13][14] In 1987 Cretin and Derham Hall merged into a co-ed facility to form Cretin-Derham Hall High School.

He also reasoned that it would be better to improve the competitive level of the public schools including the elementary and junior high sports teams.

[22][23] In March 2002 Cretin began making steps away from the Saint Paul City Conference.

[30] The most recent addition was in 1996 when the newly built Arlington Senior High School joined.

The ease at scheduling non-conference games with teams from the other division was seen as acceptable to Minneapolis officials.