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.
In 2015, Marsden entered 5 teams into this event and in addition, Emily Callam and Shwetha Wevita took part in the Scots College piece. 
This was then selected to go to the National Finals in June and Shwetha was awarded the Sam Wanamaker Award for Most Promising Actor. This allowed her to attend a series of workshops in October.
In 2013, Jessy Reese also attended this workshop and was selected to attend the Globe Theatre in London the following year.