The new funding includes £25million for the Young Londoners’ Fund, a scheme set up in 2018 to provide activities for youngsters.
Sadiq Khan will spend an extra £55million next year to tackle violent crime in London, City Hall has announced.
The Mayor has now pledged to boost youth services and police funding by more than £100m next year.
This includes funding an extra 600 police officers in the next financial year, to make up a perceived shortfall.
The government allocated London funding for 1,400 new police – less than the 2,000 extra that the Metropolitan Police claims are needed.
The new funding includes £25m for the Young Londoners’ Fund, a scheme set up in 2018 to provide activities for youngsters.
City Hall research shows that national government funding for youth services in the capital has fallen by 46% since 2011.
Mr Khan will also channel additional money to his Violence Reduction Unit, funding mentors for excluded school children in pupil referral units.
And there will be more cash for groups working at a local level to steer young people away from violence.
The rest of the funding will crack down on the County Lines drug trade, target repeat offenders, and work to reduce domestic violence in the city.
The Mayor also plans to raise money for policing by hiking up council tax.
Mr Khan has increased annual bills for policing by the maximum amount allowed by government – £10 next year for Band D properties – every year he has been in City Hall.
The Mayor says he has been forced to pass the cost on to tax payers, because government funding for policing still doesn’t cover the cost of replacing officers lost from the Met since 2010.
He said: “My plan to tackle violent crime in London means being both tough on crime, and tough on the underlying causes of crime.
“The causes of violent crime are complex and deep-rooted, but have been made far worse by huge government cuts to the police, schools, youth services and local councils.”
He added: “I am today launching a new £55.5m package to tackle the root causes of crime by reducing school exclusions, providing more mentors for young people creating more positive opportunities for disadvantaged young Londoners.”
Liberal Democrat assembly member Caroline Pidgeon said dealing with the causes of violence was a “vital ingredient” to stop London’s crime epidemic.
She said: “The rise in violent crime in London that started when Boris Johnson was Mayor and has since continued under Sadiq Khan is something that must be turned around.”
“Other cities, such as Glasgow, have shown that it can be done. It is a huge pity that we are only now starting to adopt policies that should have been in place for many years.”
The Mayor will publish his final budget for the 2020/21 financial year tomorrow, subject to approval by the Assembly in two weeks’ time.