The locker beat-down unrealistic?
Meh.
It worked for me.
Is such an occurrence less likely then 10-20 yrs ago? Sure.
Impossible? Nope.
Thousands of High Schools across the US (and Canada), some are sure to be less vigilant then others.
If this to be a series, it would be nice to see a lil' fallout from the bullying. Protective parents threatening to sue, for example.
Besides all that, I liked the story. I particularly enjoyed the way Ben's feelings for Sam snuck up on him. I also was taken by the way you wrote Ben's new found love as a source of pain, anger and conflict rather then warm and fuzzy. The way he tried to escape the very source of his attraction. Kudos.
Look forward to further exploration of these characters...or your writing in general. (Like BlindAmbition posted above, I liked the story's flow.)
Thanks for an enjoyable read.