Montgomery County Public Schools are investigating the sideline business of a high school principal who quietly operated an expensive consulting service that officials worry conflicted with his ability to lead.

Moreno “Mo” Carrasco, principal of Rockville’s Richard Montgomery High School since July 2003, shut down his operation’s Web site, Savetheprincipal.com, late last week after an investigation by The Examiner revealed he may be in conflict with the Board of Education’s code of ethics.