Arnold Holtberg, the longest-tenured headmaster in the history of St. Mark’s School of Texas, plans to retire at the end of the 2013-14 school year. Holtberg told the private school’s Board of ...

The top 25 ranking is based on an analysis of key statistics and reviews from students and parents. St. Mark’s School of Texas, an all-boy private school, grabbed the No. 1 ranking in Niche's ...