Kenilworth School under-15s booked their place in the Twickenham final of the NatWest Vase with a thrilling 32-17 win over Queen Elizabeth Grammar School, Penrith.
Kenilworth raced into an early lead at Allianz Park, home of Saracens, scoring three tries courtesy of Alex Bradley, Cameron Holden and Ardal Yallop in the opening 12 minutes.
However, all three tries went unconverted and Queen Elizabeth fought back with touchdowns from Archie Rattray and James Ellis.
Both were converted by fly-half and captain Louis Johnson to cut the deficit to a point.
With the momentum now with the Cumbrian side, an infringement at the ruck from Kenilworth allowed Johnson to slot over a penalty for a 17-15 half-time lead.
Kenilworth composed themselves at the interval and it resulted in them keeping their opponents scoreless for the second half while adding 17 points themselves.
Prop Dylan Hunter capitalised on a loose ball to dive over the line and put his side back in front before number eight Josh Marston extended their advantage in the 47th minutes, showing great strength to drive over the line.
Will Woolvine converted to make it 27-17 and the Warwickshire side made sure of their place at Twickenham minutes later when man-of-the-match Yallop went over for his second try.
Kenilworth School will meet Somerset-based Beechen Cliff, who beat London Oratory 24-12, in the final on Wednesday.