More and more children, some as young as eight, are bringing weapons to school, according to new figures obtained by ITV News London.
Between 2011 and 2015 the number of children found at school with an offensive weapon increased by 88 per cent.
In 2015 the number rose by almost a quarter. Last year, there were 286 children found with offensive weapons at school. Shockingly, 47 of those were aged just 12.
I spoke to the father of 15-year-old Kiyan Prince, a teenager who was stabbed to death outside his school in Edgware in 2006.
Mark Prince has devoted his life to combatting the rising problem of knife crime. It's a decade since Kiyan died, a talented footballer in QPR's youth team, he was stabbed with a penknife through the heart. He was defending a friend who was being attacked.
Mark now gives talks to you people about the dangers of carrying a knife. Increasingly though, he says schools are avoiding the subject - and not enough is being done to tackle the problem.
The man who has inherited these shocking figures, has now invested £400,000 pounds to tackle the problem.
I spoke to the new Mayor, Sadiq Khan, at St Mary's in Paddington, where one of the charities to benefit from that money works alongside doctors and nurses to help victims of stabbing escape further trouble.
He agrees with Mark Prince, more needs to be done in schools:
A problem which has escalated. The question is: what now needs to be done to end violence in London's schools, parks and playgrounds.