Teenagers are better behaved and less hedonistic nowadays

But they are also lonelier and more isolated

AntonioGuillem/Getty

At the gates of Santa Monica College, in Los Angeles, a young man with a skateboard is hanging out near a group of people who are smoking marijuana in view of the campus police. His head is clouded, too — but with worry, not weed. He frets about his student loans and the difficulty of finding…