Almost half of all sex offences are committed against children, despite them making up just 21% of the population, the BBC has learned.
The 19,250 offences made up 47% of the total in 2008/9, while 30% of robbery victims were minors, data from police forces in England and Wales shows.
There were also 111,000 violent crimes against under 18s, figures obtained via freedom of information requests reveal.
Victim Support says the figures do not reflect the true extent of the problem.
Many victims are unable or unwilling to report what has happened to them, it argues.
A similar survey conducted by the NSPCC in January suggested more than 21,618 sex offences - or 60 a day - had been committed against children in 2008/9.
The charity found that one in seven victims were younger than 10, while 1,000 cases involved children aged five or under, with some so young they did not understand what had happened to them.
The latest figures, obtained by BBC Radio 5 live, suggest youngsters are the victims in 15% of violence cases.
But Paul Fawcett, from Victim Support, said there was now a level of acceptance of violence, especially among gang members, which never appears in the official statistics.
"In terms of the prevalent culture among some groups of young people, being a victim of crime is considered the norm," he said.
Research conducted by other organisations suggested initiation rituals involving certain kinds of attack were "par for the course" in terms of proving gang membership, he added.
A government spokesman said: "Young people are more likely to be victims of crime which is why this government is determined to work with police and local agencies to tackle the issue".
One 14-year-old described being attacked by a gang of 10 youths.
The youngster, who we are naming only as TJ, said the youths had approached him in a south London park and demanded he hand over his belongings.
He gave them his MP3 player, keys, rail card and phone.
"I turned around and got punched. It made me fall to the ground and I blacked out," he told BBC Radio 5 live's Victoria Derbyshire.
His friends told him later that he had been beaten, kicked and stamped on.
The attack left him with a ruptured spleen, swollen internal organs and needing three blood transfusions. He was put into a coma for 48 hours to help his body recover.
"They are quite sad and vicious and disgusting," said TJ.
"I didn't deserve that. I gave them my things, they didn't need to do anything else.
"Maybe it was because it was their area and I was in their turf and they attacked me for that, or probably for fun as well."
In the six weeks since the attack, he has left the house just three times, he added.
The British Crime Survey is seen as the most authoritative indicator of the level of crime in England and Wales.
However, until last year it only interviewed people aged 16 and older about their experiences of crime.
That has now been extended and from this year the figures will include children from 10 years old.
Charities hope this will finally give a truer picture of how young people are being affected by crime, beyond the official police statistics.