Most children have been frightened of being picked on by the school bully at some point in their lives.

But when it happened to Jeff Kinney he was saved by the bell. And he’s created a £300 milllion business on the back of it.

American author Jeff, whose Diary Of A Wimp Kid series of books regularly features in Britain’s best-seller lists, is on his way to Birmingham’s New Alexandra Theatre for a theatrical signing show.

He says can hardly believe how his own success has put him on first-name terms with successive US Presidents.

And he says that it all started with a bully.

“I come from a very ordinary background and write about ordinary things,” he says. “I was in a fist fight once. I didn’t enjoy that.

“Then a bully lined up the weaker kids and started punching them one by one.

“It was about to be my turn when I was saved by the school bell, and he forgot about me.”

As a father of two sons – Will, aged 11, and Grant, who is eight – Jeff has bigger worries now than the mere presence of a bully.

In the US, a succession of spree shootings has changed life in the playground for his boys.

“They have to have lockdown drills, where the school is literally locked down and everyone stays very still behind closed doors and hides under desks,” he explains.

“I guess it’s very similar to the kids who grew up in fear of the atomic bomb, or Russia invading.

“But you just never know when the lesson they learn might save lives.”

Jeff is already one of the fastest-growing authors in history since his first book was published in 2007.

The eighth Diary Of A Wimpy Kid book, Hard Luck, went on sale on November 6.

It shot to the top of every bestseller list – for children and adults – and relegated Sir Alex’s autobiography into second place.

Jeff says that, once he sat down to create the everyday adventures of his 12-year-old hero, Greg Heffley, he knew he was on to a winner.

He spent nine years creating the gag-laden formula, refining the drawing technique that had failed to find him a dream career as a newspaper cartoonist.

Now 42 and married to Julie, he still lives in the same house in Plainville, Massachusetts, a small town of less than 10,000 people north east of New York.

He has retained his day job with Pearson publishing – so it takes him nine months to complete each story at night.

As well as being the brains behind the children’s website Poptropica, sales of his books have increased exponentially and three movies have grossed more than £125 million.

“That’s not what I see,” Jeff quickly points out. “But that’s what it all generates, and across all of the different countries it employs some 500 people.

“There won’t be any more movies for now because the child actors just got too old.

“My books are about a sliver of two years in ‘junior high’ – that’s between the ages of 11 and 13 – when I always felt children were sort of shifted off to the side to incubate, and that it was quite scary to be in that environment.”

Does he write as a boy trying to find a man’s brain or as a man trying to find a boy’s brain?

“It’s the latter,” says Jeff. “It took me four years to get there. Having children of my own helped, though I wish I could get more direct information from their experiences.”

  • Diary Of A Wimpy Kid is at the New Alexandra Theatre Birmingham at 6.30pm on December 4. Details and tickets at www.atgtickets.com