I wasn't always a musketeer. [Although this is veering towards his past and he's always been touchy about that, regardless of how sweet Sakura herself is.] School's mostly for noblemen, for those who intend to enter the service of the church. [And then it's less math and science and more history and scholarly texts, which he isn't opposed to learning about, either, but obviously he was not bound for the ministry :'|]