Duncan Harrison, 15, from Horfield, wrote an inspirational speech on the rights of children, following a trip by the final three contestants to Malawi.
He also trains at the Actor's Workshop in Flax Bourton.
His first performance will be on the 15 May 2009, at Redwood Lodge, for the Sarah Lacy Fund Ball, celebrating young talented performers around the West.
"For some things you had lots of time to prepare, whilst for others everything was done on the spur of the moment. It has been quite a journey," said Duncan.
Clara Marullo, director of the Actors' Workshop said: "I am absolutely delighted to see Duncan has grown throughout the competition. Acting and public speaking are the same - you need to be truthful, spontaneous and subtle."