Books

It of course depends on your students, but I'm just gonna chime in that I read 1984 in 9th grade, so I would have been 14 years old, only a year older than your students. It was admittedly an honors English class, but depending on their skill and maturity I don't think that you necessarily need to avoid it as an option. Maybe not as a take-home book for them to read on their own, but maybe as one to read in class to sort of guide them through and challenge them a bit.

I don't know much about "kids these days," it's been 20+ years since I was their age, and probably around 10 years since I reread 1984, but nothing in my memory sticks out as something I would have been too bothered by as an older middle schooler and honestly probably pretty tame compared to some of what we were watching and reading on our own time (if I recall, the original Saw movie came out around the same time and I remember seeing it)

Again, you certainly know your students better than we do, but I assume that "dystopian literature" isn't a required course but some kind of elective, and your students are signing up for it and probably wanting to experience some darker and more adult themes, otherwise they probably would have chosen a different class.