Teachers who cannot understand pupils' tastes in music and clothes now have a handy guide from a yoof-conscious Government.
The report examines 10 teenage "tribes": Indies, Moshers, Sporties, Trendies, Townies, Geeks, Scallies, Gangstas, Skaters and Goths.
Many are easily identifiable. Goths, with their penchant for black clothes and gloomy music, are simple to distinguish from hip-hop-loving Gangstas, who are not usually criminals.
A preference for hip-hop "may not define completely which tribe a young person belongs to but the music at a gig full of Goths will undoubtedly sound different from that populated mainly by Gangstas", the report states.
The study, based on a survey of 1,000 teenagers, says there are also sub-tribes such as Smellies, a sub-species of Mosher who like even heavier metal.
The study's chief finding was that one in five teenagers believed friends had pretended to take drugs to impress others. Perhaps unsurprisingly, Gangstas were most likely to show off in this way.