Green Eggs and Ham is often read as an allegory for overcoming irrational prejudice. Just tell your kids that—they'll know what we mean. Next?
Oh, you know we always have more to say. Let's break it down:
Irrational prejudice: Green eggs and ham are gross because they're green.
Overcoming prejudice: Try the green eggs and ham, find out they're pretty tasty. Voilà!
Sure, this interpretation assumes that ham and eggs in Seussville aren't normally green and that the big guy is afraid of them because their color isn't quite what he's used to. But we're going to assume away, because we know Seuss was a very socially conscious guy, one who was very concerned with irrational prejudice. (See, um, any other book he ever wrote.)
In fact, Seuss was kind of an expert in irrational prejudice—on both the giving and receiving ends. Often mistaken for being Jewish, Seuss wasn't a stranger to anti-Semitism. But even as he was fighting against such anti-Semitism during World War II, he was exercising some irrational prejudice of his own. Just take one look at his political cartoons to see how he depicted Japanese and Japanese-American people (source). Not very nicely, to say the least.
Seuss learned his lesson well, though; an anti-prejudice spirit can be found in most of the books we read and love today.
If we want to get a little less political, we can see Green Eggs and Ham as a don't-knock-it-till-you-try-it kind of a story. The only thing the big guy doesn't like about green eggs and ham is that he's not familiar with it. All he needs to do is try it, and—wouldn't you know—he loves it.
The next time you turn down macramé camp because it's too girly or you change the station on Rascal Flatts because you're so sure you don't like country music, just remember Green Eggs and Ham—and maybe you'll change your tune.