Leeds' team included another future Super League winner in Nick Scruton.
Stuart Reardon, Rob Parker and Jamie Langley played for Bulls in both finals.
Leeds' academy trailed 1-0 at half-time, to a Chris Bridge drop goal, but Peter Lupton kicked them ahead with a penalty goal seven minutes after the break and substitute Damien Kennedy scored their opening try.
Bridge pulled two points back for Bulls before McGuire touched down to make it 10-3 with six minutes left. Reardon crossed for Bradford soon afterwards, but Leeds held on.
Rhinos' team for the 2002 academy Grand Final was: Richard Mathers, Austin Buchanan, Andy Kirk, Dwayne Barker, Mat Gardner, Danny McGuire, Jon Hepworth, Ewan Dowes, Jon Wainhouse, Tommy Gallagher, Jason Netherton, Ryan Bailey, Peter Lupton. Subs Rob Burrow, Craig Stanley, Nick Scruton, Damien Kennedy.
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