Why did the student get sent to the library during science class?

This joke tickles our funny bone through a clever mix of wordplay and situational absurdity. We expect a student in science class to be engaged in experiments, learning about chemical reactions, or perhaps dissecting something fascinating. The idea of "inventing" usually conjures images of groundbreaking discoveries or complex machinery. So, when the punchline reveals the student's grand scientific pursuit is merely finding a novel way to turn a book's pages, the mundane nature of the task creates an unexpected, humorous twist.

The real-world context here is the stark contrast (Review) between the ambitious goals of science and the simple, already-perfected act of turning a page. Libraries, by their nature, are quiet places where books are handled with care, and the standard method of page-turning is universally accepted. Sending the student to the library, where such a low-stakes "invention" would be less disruptive (and perhaps even more ironically fitting for a place full of pages), perfectly caps off the joke's silly premise. It highlights how sometimes, the most basic solutions are already the best ones.