Almost a third (31 per cent) of 14-year-olds have shoved, hit, slapped or punched someone, academics found.
Meanwhile, more than one in 10 14-year-olds admitted to binge drinking.
New analysis of data from the Millennium Cohort Study, a study tracking the lives of thousands of pupils born in the UK in 2000-01, found that rates of assault were significantly higher among boys (41 per cent) than girls (21 per cent).
The authors wrote that the overall proportion was "surprisingly large".
In addition, 1 per cent said they had assaulted someone with a weapon.
Experts from the Centre for Longitudinal Studies, part of the UCL Institute of Education, analysed data on risk-taking behaviour among 11,000 14-year-old pupils.
Around 14 per cent of teenagers had caused a public nuisance – such as being noisy or rude in a public place – at least once in the previous 12 months.
And around one in five pupils had had some contact with the police by the age of 14. Just under 10 per cent had been stopped and questioned, while around 8 per cent had been cautioned or given a formal warning. Just over 1 per cent had been arrested.
Researchers also found that, by the time they were 14, half of British teenagers had experimented with alcohol, smoking or drugs in some way.
Boys tended to have first tried alcohol at a younger age than girls: one in five boys had drunk alcohol by the age of 11, compared with one in seven girls.
After comparing pupils’ responses aged 14 with those they had given three years earlier, researchers found big increases in the rates of binge drinking. Binge drinking was defined as having had five or more drinks at a time on at least one occasion.
Fewer than 1 per cent had been binge drinking by age 11, compared with almost 11 per cent at age 14.
The study also showed that the earlier pupils began to experiment with risky activities, the more likely they were to continue. Of those who had tried smoking by the age of 11, 25 per cent were regular smokers by age 14.
By contrast, 15 per cent of those who had tried their first cigarette between the ages of 12 and 14 were regular smokers by age 14.
Professor Emla Fitzsimons, one of the authors of the research and director of the Millennium Cohort Study, said: "Our findings are a valuable insight into health-damaging behaviours among today's teenagers right across the UK.
"There is clear evidence that substance use increases sharply between ages 11 and 14, and that experimentation before age 12 can lead to more habitual use by age 14.
"This suggests that targeting awareness and support to children at primary school should be a priority."