The Board of Education has begun interviewing candidates to replace principals for San Marino High School and Huntington Intermediate School. Gary Richards, principal of the high school, has been named assistant superintendent for instruction, replacing Ken Ogden, who will retire in June after working in the district for 25 years. Tom Parisi, Huntington school principal, left in April to be instructional dean at Orange Coast Community College. Supt. David Brown said the San Marino Unified School District has received about 20 applications for each position.