Kevin Giblin, who coached Georgetown Prep boys’ lacrosse for the last 27 years, has resigned. (Toni L. Sandys/The Washington Post)

Georgetown Prep accepted the resignation of lacrosse coach Kevin Giblin, who led one of the nation’s top high school programs for the past 27 years, Athletic Director Dan Paro confirmed Wednesday.

In an e-mail sent to the school’s lacrosse teams and parents and obtained by The Post, Paro wrote that offensive coordinator Charlie Horning was named interim coach and much of Giblin’s staff is expected to return for the 2015 season.

Giblin became Prep’s second head coach in 1988 and has since led the Little Hoyas to 10 Interstate Athletic Conference titles and 14 top-25 national finishes. He guided Prep through a 19-1, IAC championship season in 2014, one in which the Little Hoyas were wire-to-wire No. 1 in the Post’s Top 10 and featured All-Met Player of the Year Charlie Horning (the assistant coach’s son). In 25 years of that Top 10 poll, Georgetown Prep finished in the rankings every season and at No. 1 eight times.

Giblin’s teams have won more than 400 games in his tenure, and Prep is one of the more well-represented schools on college lacrosse rosters: More than 220 players have gone on to college lacrosse during his tenure, including 36 high school all-Americans.

“Coach Giblin built the Georgetown Prep lacrosse program into a national program over 27 years, and we thank him for his hard work, dedication and genuine commitment to his players, the alumni and the entire Georgetown Prep community,” Paro said in an e-mail.