Mark has spent a considerable portion of his career directly developing and supporting hundreds of school leaders throughout the U.S. as Executive Director of multiple organizations.

He has advised and led educational efforts all across the country as well as served on multiple boards, including the Council of Chief State School Officers and Chiefs for Change. He began his career as a teacher, and as principal went on to lead the dramatic turnaround of a low performing school.

Mark was the Secretary of Education in Delaware. During his tenure, Delaware youth significantly improved their academic achievement, college access and success soared, high school dropout rates reached the lowest point in history, and the high school graduation rate increased to a record level.