It's one of the most important works in science of all time. It's at least as important as evolution theory and the theory of the atom. Kids these days spend too much time memorizing different types of minerals, and other random scientific facts. Obviously they would not know what a manifold is, as they wouldn't have the math. But so what? Thinking of spacetime as curved by under presence of mass, even if it's just memorized that it is so and not well comprehended, provides more valuable knowledge than memorizing a thousand minerals. Not knowing the nature of gravity is like not knowing organisms are made of cells. It's just too fundamental to ignore.