The investigation, carried out by the Crime Prevention Council (Brottsförebyggande rådet, Brå), found that crime levels among ninth-grade students around Sweden have improved drastically since the mid-nineties, a trend that appears to be continuing.
"One theory is that they're at home and sitting in front of the computer, socializing via the internet," Jonas Ring, an investigator in the report, told the TT news agency.
The study found that one in three 15-year-olds has played truant, that every fourth has vandalized something, and that one in five has shoplifted.
Furthermore, two out of every five have been drunk and one in 20 has smoked cannabis.
However, despite these statistics, the trends indicate that ninth-grade students are actually behaving much better than they were in past decades.
In 1995, 32 percent of 15-year-olds admitted to having vandalized public property. Tuesday's survey showed that this figure had dropped to just 16 percent.
While the report itself did not venture into details as to why the youths are not playing up as much, factors such as their meeting places suggest how their attitudes are evolving.
"We can say that fewer students are meeting their friends at nighttime," said Ring.
He pointed to the idea that youth crime is often committed among friends, and with the groups of teens more likely to stay home, they're less likely to be "hanging around on street corners".
Patrick Widell of the Stockholm City Police also reasoned that the home front could be responsible for the behavioural improvements.
"If you're sitting at home, you're not misbehaving - and you're not drinking either," he said.
"Youths without parents to make the rules are more likely to have problems and they are the ones we're finding in strange places at odd times."
He added that police even have a better cooperation with the social authorities today.
"It's easier for us to notice youths in the danger zone which makes it simpler to help with their situation," he said.
The study was based on a survey of 6,500 ninth-graders.