Yes, I did know that the Risch algorithm existed; and I've implemented it (or at least most of it).
I wonder why it's never mentioned in high school Calculus classes.
Because there's no way in hell that you want to ever apply the Risch algorithm by hand. As the wikipedia page says, it takes more than 100 pages to describe the algorithm; even just using it to compute the integral of x + 1/x would probably take hours without a computer.