An intrepid high school newspaper has landed an interview with Defence Secretary James Mattis after calling his leaked mobile number.

In May 2017, the Washington Post ran a photo of Donald Trump's bodyguard Keith Schiller walking with the President, carrying papers that showed a note on top with Mr Mattis' number scrawled on it.

Though the paper took the photo down quickly after realising the accidental exposure, Teddy Fischer - a second year student and staff reporter at Mercer Island High School in Washington state - saved the image.

Teddy called Mr Mattis and was granted an interview along with his editor Jane Gormley by the Defence Secretary himself, who spent his early years in Washington state.

Ms Gormley almost did not believe Teddy's claim, but Mr Mattis then called back three times to schedule a date and time for the conversation.

The Islander newspaper ran three accompanying pieces, including one of Teddy's personal experience and Ms Gormley's reflections.

“I speak the same to high schoolers, college grads, or congressmen...I’ve found high schoolers to be plenty bright,” Mr Mattis said.

“So, I’ve always tried to help students because I think we owe it to you young folks to pass on what we learned going down the road so that you can make your own mistakes, not the same ones we made,” Mr Mattis said in the interview.

Questions covered a wide range of topics from political ideologies, future military conflicts, foreign diplomacy, global development, and Isis.