The marketing of such a show to a demographic including twelve-year olds is despicable.
However, the notion that high school students are “children” is a legal and social fiction, rather than reality. Biologically, most high school students are sexually mature, and in an earlier time would be married, working and raising families, rather than encouraged to remain childish almost indefinitely by a society this is at once sentimental in wanting to extend childhood and callous in trying to keep wage rates up by keeping young, biological adults, out of the labor market on the plea of educating them—something our high schools seem to do less and less of with each passing year.
The content-free nature of much of high school leaves those who don’t care, or who can do all the work in the odd study hall with plenty of time for idling and vice. (Even the college-prep track has been watered down from back in my day, and even then, I could do all the work in study hall, the odd term paper excepted, and even then had time for idling—blessedly my preferred vice in those days was hex-grid wargaming rather than booze, drugs or wenching.) More distressing in some ways than the marketing to 12 year olds is the fact that to some extent this is “art” imitating life.
The key idea here is that previous teenagers were married, working and raising families, IOW, using their sexuality in a pro-social manner. In modern media portrayals, teens behave like adults but have the responsibilities of children proper.