As undergraduate and graduate programs get more and more interdisciplinary, it does not seem that high schools are following suit. The traditional high school curriculum is still strictly divided into academic subjects: English, history, math, science, foreign language and the arts. Students are generally not encouraged to find connections between what they're studying in AP US History and the novel they're reading in their English class, even though the parallels between the real and fictional worlds can make for both fascinating discussion and scholarship-worthy term papers.
It's true, of course, that many parallels can be drawn between math and science. Students are encouraged to take chemistry at the same time as advanced algebra, and physics at the same time as trigonometry or pre-calculus, but these connections are more difficult to find in the humanities and fine arts, even though there plenty of opportunities to connect math with music or visual arts, and physics with physical education, and chemistry with home economics. For whatever reason, many traditional high schools like to keep their classes and notions separate.
More progressive schools will now combine English with social sciences into a double-period course that is frequently referred to something like a "humanities core," but it's just as likely that a student will read The Crucible at 8:00AM in Honors English and learn about McCarthyism in AP US Government at 2:00PM and not make any connections between the two at all, though there are plenty to be drawn.
A lot of literature was written in response to things that were happening in the world at the time. Jane Austen wrote her novels to provide social and economic commentary on women's role in society; as an intelligent and insightful, yet noticeably unmarried (though briefly engaged) woman, Austen lamented the fact that marriage was a woman's only route to social and financial independence, unless she happened to be born wealthy like literature's favorite spoiled daddy's girl, Emma Woodhouse. Huxley's Brave New World can be seen as cautionary tale along the lines of George Orwell's 1984, but a student well-versed in current events might actually decide that the book is simply holding a mirror up to society and showing the world what it already is.
This isn't to say one interpretation of literature is more valid than another, but that when students are shown connections between things that they are studying, they could be motivated to try to make some of their own. Math and science is about finding the "right answer" and understanding the world as it is, but the humanities and arts are about helping students find themselves and to envision the world as it could be, and maybe even inspiring them to go out and make that better world.
It also might inspire students to try harder in their classes. While discussing a Lord of the Flies summary in class, students could draw parallels between Ralph and Jack's struggle for the title of chief and the 2000 Presidential election. If students are asked to understand what they read, and not to simply regurgitate names, dates and facts, they'll be more likely to complete their assignments in the first place.