I was in eighth grade when I first read John Steinbeck's Of Mice and Men. I don't remember particularly liking the novel because of the ending, but I found myself constantly thinking about it for a few weeks afterwards. In particular, two images kept coming to my mind: the dead mice and the dead woman. It just seemed so strange to me that those were the big images that stuck with me. The woman is less surprising. It's an intense scene where slow Lennie proves that he does not know the limits of his strength even when dealing with another human being. Combined with the mouse, I was beginning to wonder what was actually drawing my interest in the work.
Upon a recent rereading, it finally clicked for me. It's not that Of Mice and Men is a particularly violent novel. It's how the minimal amount of inferred violence is used to create a believable and compelling relationship between George and Lennie.
Lennie is essentially an overgrown child. He's constantly testing his limits against the myriad of seemingly arbitrary rules George sets up for him. "Don't drink the water, Lennie. Don't keep dead animals as pets, Lennie. Don't say a word to anyone other than "yes sir," Lennie." Every time Lennie steps out of line, George is there--like a particularly resilient teacher or tough-love parent--to put him back in place. The little mouse with the fur rubbed right off its head is just the first sign that something has to give in this relationship.
These are clearly two men who care for each other like they're actually brothers. They work together, they travel together, they eat together--they do everything together. George is constantly trying to protect Lennie from himself and the rest of the world. In some ways, he doesn't have another choice. Lennie is too slow to understand the nuances of society and never grew past the stage where little boys pull apart their toys just to see if they can do it.
The destructive imagery is a further extrapolation of the relationship. In the same way that George can only do so much to stop Lennie from causing trouble, Lennie can only control himself for so long before he winds up hurting something. He genuinely cares for the living things he accidentally kills. He tries to make it right by apologizing and petting them gently. He just gets so excited trying to be just like George that he loses control. It's a sad cycle that does have staying power in the mind.
While I'm not sure that Of Mice and Men is the kind of work students should be reading before high school, it is a novella that has a good bit of interest and style to push a distinctly American viewpoint. George is willing to fight against anything to save his friend Lennie, even if it means sacrificing his own security and well-being. He will not abandon the man for making simple mistakes. His final actions are not an effort to give up on the fight, either; they're an attempt to finally make things right for Lennie. It's a sad way to end the story, but it's the only way Lennie's story could end. Destruction brings destruction, even if it was only an accident.