The new south light rail line passes near two high schools and Sacramento City College. No surprise that lots of teenagers ride it.
Teens often travel in packs, a dynamic that can lead to unruly behavior. What's merely annoying at times loud music and cursing   can become dangerous. There have been a few fights and at least one stabbing on the south line.

Even when they aren't doing anything wrong, rowdy teenagers can intimidate older riders. RT can't afford to station a cop on every car. It needs help from school officials.  So, just as RT responded when the Sacramento City school board lobbied for cheaper student fares, now the school board needs to step up to help RT. For example, during school commute hours, the board could assign school monitors to light rail stations or even put them on trains to supplement RT security.

The monitors can impose sanctions   including in school detentions or Saturday school   that RT cops can't. Beyond sanctions   their presence alone can have a positive effect on student behavior.
I don't want to end this on a negative. Teenagers represent a challenge, sure, but they are a huge opportunity as well. If this community is to clean up its air and unclog its roads it will need to attract more young transit riders. We just want them to behave. 

Ginger Rutland writes for the Sacramento Bee Opinion pages.