The Lisburn-based school achieved the landmark feat after a 24-15 win over Royal School Armagh at a packed Kingspan Stadium.
After five near-misses in the competition, there would no further heartache this time around as Rio McDonagh (2), James Gould and Luke Dillon scored tries for Wallace.
Here’s some of the best action and celebratory shots from the day.
13. Schools' Cup Final
James Gould of Wallace scores a second try during this afternoon’s final at Kingspan Stadium Photo: Andrew McCarroll
14. Schools' Cup Final
Will Boyd of Royal School plays a box kick during this afternoon’s final at Kingspan Stadium Photo: Andrew McCarroll
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