John Weeks is the current Headmaster of Knox. He joined the school in 2004 and has been at the forefront of many major initiatives and building projects, including the Knox Great Hall and Aquatic Centre. He has also been responsible for many new initiatives, such as the Positive Psychology. Before he was Headmaster at Knox, he was the Founding Headmaster of Hunter Valley Grammar School (from 1989 to 1996) and the Headmaster of The Illawarra Grammar School (from 1996 to 2003). He has also taught History.

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