Some teenagers have kept pictures of their knives
Children as young as seven are regularly carrying knives, according to a BBC investigation.
The BBC's Panorama programme spoke to a group of young people in a project that helps teenagers who have fallen out of mainstream education or who want to undertake extra work.
The frank conversations with children in the Youth Education Support Service (YESS) in London revealed that knives are increasingly becoming a part of everyday life for many teenagers.
All of the children Panorama spoke to said that they don't carry knives.
Laura, who says she hasn't been to school since the age of 12 after being threatened by a knife, said kids carried knives because they were easy to get hold of.
"Knives are more at the top of the list than guns at the moment, because it ain't kids our age that's carrying guns. Where would you get a gun from?" she added.
Friends of hers admitted it was very common for children to carry knives - in fact they claimed to know of one who had a pocket knife at the age of seven.
And David, who wants to be a laywer when he grows up, gave a shocking answer when asked how many of his friends had had a knife pulled out on them.
"All of them, all of them."
Although the children at the YESS project said they don't use knives, they were clear that the threat of violence was an ever-present danger and knives were needed to make people feel safe.
Another girl in the group, Sofia, said: "Well, most people wouldn't really care to use it, cos it's like it wouldn't make them feel guilty or nothing.
Children as young as seven have carried knives
"It's just if they get caught then they'd be bugged, they're just scared of getting caught not the actual thing of doing it."
Charlotte, told Panorama that she briefly carried a knife after being threatened with violence by a group of girls.
She said: "I've got to have something with me, innit. And one of my friends said to me "Oh take this" and that's for your protection."
Laura, said that she had seen some serious weapons being wielded by youngsters, adding: "I've seen someone carrying but two knives, and do you know what, they weren't even knives, these were like Chinese chopper things.
"I ain't lying. You could put your hand in and they were like a blade saw, but they were long, and they weren't blunt, they were sharp."
But for some of the children, knives are clearly more than self defence. Chantelle told the programme that it is very common for some people to use them for mugging.
"It's easy for them just to get a knife, pick it up, put it up to someone and say "Give me your phone" or whatever and the person will actually give it to them because they're terrified so that's what happened."
But the most chilling message came from a teenager called Jamie-Lee, who said that most parents had no idea of the level that the knife culture was at.
She said: "Most parents probably don't even know their son or daughter is carrying a knife to school with them or going out robbing cars or motorbikes or whatever they're doing.
"Most parents don't have a clue. They don't have a clue till the police drags them back to their front door."
Panorama: Your child's been stabbed was broadcast at 22:15 BST on Sunday, October 17 on BBC One.