The pupil looked shocked as the bully with a broken nose and tattoos stood over him and yelled: "Give me your shoes."
The confrontation happened in a tiny graffiti-strewn prison cell. Outside the pupil's classmates stood giggling, watching on a TV monitor.
Prisoners and officers from Britain's oldest jail staged the scene at Whitstone community school in Shepton Mallet, Somerset, to show pupils the harsh reality of prison life to deter them from crime.
The 9ft by 6ft prison cell was built by inmates of Shepton Mallet's category C prison, and set up in the school hall.
The part of the bully was played by a prisoner - 30-year-old Martin Trent, who is serving a two-and-a-half year sentence for making threats to kill.
The giggling ceased when he told pupils: "If that had happened on the wing, I would have kicked him all round the cell. There's bullying in prison just the same as at school. Except there's nowhere to run in prison."
Meanwhile, prison principal officer Ceri Mortimer lined up a group of Year 11 pupils and began to treat them like new inmates.
"Don't speak unless you're spoken to," she told one pupil sternly, handing him a pair of green overalls. From now on you will be known as 2674 Anderton - that's your prison number."
Pupils were also shown an inmate's kit, from clothes right down to prison-issue nailbrush.
Steve Chaudoir, Whitstone's head, said: "The probation service contacted us as part of their work to show youngsters how prisons really work. Shepton Mallet prison is our next-door neighbour and these youngsters walk past it every day."
He said every parent was contacted before the visit. "Obviously we made it quite clear that we would need to know who the prisoners were before they came into the school and that they weren't from the maximum security wing."
One of the three inmates, Franco Bellusci, aged 35, has only four months left of a three-year sentence for burglary.
He said: "It lost me my wife - I lost everything. That's why it's very important for me to get the message across to these children. We're showing the harsh reality and I think it's making an impression on them."