Documentarians Parker Hill and Isabel Bethencourt follow around a group of Texas trailer park kids for a year in “Cusp,” an eye-opening vérité film about the angst, struggle, and heartbreak of being a teenager. It’s a shame that the film’s subjects aren’t very interesting, because there are some very disturbing and provocative discussions and events shown on camera that detail the sad reality for many young women in America today. One thing this film does is reiterate the fact that parental responsibility is vital to raising strong, confident adults. Most of these girls don’t have adequate supervision, living their lives as they see fit. Beneath the underage drinking and nonstop pot smoking is a disturbing undercurrent of sadness and restlessness, and a depressing reality that these kids will likely face limited options for a bright future. Even more disturbing is the frank manner in which sexual assault is discussed, with many of the girls talking about rape in the most nonchalant way. It’s upsetting and unacceptable that today’s teenagers aren’t being taught to command the emotional strength to say no when they’re being pressured to do something they don’t want to do. A lot of this behavior can be attributed to the antiquated gender roles (one girl says her dad treats their home like it’s solely his castle). These formative years can make or break a person, and society needs to step up and work on that if their own parents won’t. “Cusp” isn’t a great documentary, but it reveals an intimate portrait of modern-day adolescence.