David E. Skaggs, executive director of the Colorado Department of Higher Education, resigned Friday, after less than three years in office, citing a conflict with Gov. Bill Ritter, The Denver Post reported. The Post did not have details on the conflict, but noted that a draft strategic plan for higher education in Colorado, prepared by Skaggs, has upset some college presidents. The plan would create financial incentives for colleges to improve student performance, but some campus-based officials believe the proposal asserts too much state authority.