It's important to remember that most young people DON'T carry knives.
Occasionally, some people do because they think they need it for protection.
But all the experts Newsround's spoken to agree, carrying a knife does NOT make you safer.
Pc Nigel Smith, who works with young offenders, explained why...
- There's a possibility you'll get arrested.
- If other people know you carry a knife it can cause you a problem.
- If you pull out a knife, it could be taken from you and used against you.
- If you pull out a knife and use it on another person, and hurt them, that is a very serious offence which could end up with serious punishment from the courts.
Is it always illegal to carry a knife?
Carrying any knife for your own protection or as a weapon is against the law.
Never carry a knife to defend yourself
And it is also against the law to carry a big knife - where the blade is longer than 7.62cm.
A smaller knife with a small blade, like a pen knife, is not always illegal.
It is if you are carrying it to protect yourself or use as a weapon. BUT, if you're going fishing and have a pen knife in your bag to use while you're fishing, it's not illegal.
Likewise, if you're using a craft knife in a craft lesson that's fine, but if you carry that knife to protect yourself or want to use it as a weapon then it is illegal.
What happens if you get caught carrying a knife?
Children are treated very much as adults are if they're caught carrying a knife.
You will be interviewed at a police station and asked why you are carrying that knife.
You can get a police warning, but with the concern over knives lately, you could also get sent straight to court because carrying a knife is a very serious offence.
What are the effects of being involved with knife crime?
Carrying a knife impacts on people's lives.
Your family will know if you get caught
Not only do you have to go through the police procedure, but your family have to know that you have been prosecuted for carrying a knife.
You get a criminal record for carrying a knife and that can stop you getting certain jobs in the future.
For some jobs, like working with young people, police checks are made on people's background and your chance of getting that job can be affected if you have got a criminal record.
If I have a knife I want to get rid of, what should I do?
Speak to a responsible adult, either in your family or your extended family, and get advice on the best way to dispose of it. Hopefully they will do it for you.
If you don't feel happy with that, there are occasional knife amnesties at police stations where you can drop knives off in special bins outside police stations.
Or you can always go into a police station, hand a knife over and they will get rid of it.