Northampton's young people are being shown the dangers of carrying a knife and how they lead to harm, prison and death.
The #SaveLivesNoKnives appeal is showing teenagers in the town what the law says about knives in public - and how carrying a blade will put their own life at risk first.
It includes a demonstration using water bottles of how little blood someone needs to lose before they become critically ill and how even the pressure need to press a doorbell is enough for a knife to cause serious injury.
It comes as weapon offences in Northamptonshire reached an all-time high in the past year, with 557 offences of possessing a weapon between Oct 2017 and Sep 2018.
The presentation by the Youth Offending Service and Northamptonshire Police, and organised by the borough council, visited Northampton International Academy yesterday (November 27).
PC Anne Geddes, who led the presentation, told the pupils: "I can't begin to tell you how many times young people have been arrested for carrying a knife and every time they say 'it's for self-defence.
"It's not an excuse. If you tell that to the magistrates they won't believe you and you will be punished to the full extent of the law."
The presentation explored police stop-and-search powers, the law surrounding carrying a knife and what prison sentences it carries.
The talk even referenced the case of Northampton 17-year-old Liam Hunt, who was stabbed to death in February 2017, in a knife fight only four streets away from the school.
Deputy head girl Alicia Adeleye, in year eight, said: "In movies, it looks like it has to be a full-on fight to hurt someone. It's hard to think that even the smallest knife wound can kill someone."
Another pupil, Samuel, said: "I got butterflies and felt nervous thinking about all the situations that could happen. It was scary to think about."
The #SaveLivesNoKnives project was created to teach young people there is never a reason to carry a weapon.
PC Geddes said: "Knives do not make you safe. The consequences are serious for everyone involved.
"If we can prevent the death of even one young person it will be worth it."