Alan Zilberman, Special to The Washington Post Although well into his 70s, the French post-New Wave filmmaker André Téchiné proves to be a shrewd observer of adolescence with “Being 17,” his drama about two young men and the connection they forge over a long, difficult school year. What elevates the film is not just its beautiful setting in the French Pyrenees but also how the beautiful mountain exteriors serve as a metaphor for characters’ inner lives.