The wizards learn magic at Hogwarts, but what about "normal" education. Muggles learn English, Math etc. Is this not noticed when they make contact with muggles that they can't do basic math that you learn from age 11 and up. Do Hogwarts teach the kids things that are in the normal curriculum for those ages, or is it something that they do on their spare time? Or is this something that is considered irrelevant for wizards?
We see that Hermione is taking a math type class. Otherwise the education you receive by the time your 11 is sufficient for the rest of your life. They take science classes through herbology, potions, care of magical creatures. They obviously have to be able to read as they are reading hundreds of pages of books written 100s of years ago and the more you read the better you get at it. you don't need an English class to learn how to write you just need 1 professor to be able to do corrections on your papers that you learn through experience. So they really don't need anything else, they rarely interact with muggles, and how often to you go hang out with your friends and your like hrm... lets do some quadratic equations.