Since the 1990s, Marsden has been involved in the annual Sheilah Winn Shakespearean Festival held in Wellington. Students have the option to perform in a piece directed by an adult (duration 15 minutes) or to perform their own student directed piece (duration 5 minutes). Pieces may be adapted in any way the students see fit, but must retain the original language of the play.
The competition usually takes place towards the end of Term 1, with top performers from the regional events heading to a National Festival later in the year.