Maus, by Art Spiegelman, was the first graphic novel I ever read. I was about twelve, I think, and I snuck it out of my brother's collection of comic books. There was just something different about it that caught my interest: it was a real book, heavy, with binding and a hard cover. Yeah, it was a comic book. But it wasn't like the Spiderman or Superman comics that I'd glanced at and found boring. It was a new way to look at a sad, serious subject: the Holocaust.
Like any other Jewish child, I'd learned about the Holocaust over and over. I'd been to museums, watched documentaries, and read books like Anne Frank: the Diary of a Young Girl. But when you learn about something without firsthand experience of it, it's hard to truly empathize, to truly understand what happened and how relatives who died might have spent their last days. But by changing it into something really over-the-top, with Germans drawn as cats, and Jews drawn as mice, Spiegelman actually made the narrative of his father's experience something that far more realistic, far more graspable and imaginable, than any other medium I'd tried before. So if you're learning about WWII in school, have Jewish connections, or just want to read a comic book that pushes the boundaries of what comics are, check out Maus.
Note: this book is divided into two parts. There are a few different editions available, so just make sure you read books I and II in the correct order. There's even a new MetaMaus with additional information about the author's creative process.