The BBC occasionally flirts with educational tv, and usually does a fairly good job of it too. As well as all the amazing nature docs, they do quite a bit of sciencey stuff now (usually presented by the ubiquitous Professor Brian Cox, but he is fairly likeable).
One of the tv high points for me last year was Andrew Marr’s History of the World. I’ve never been much of a history fan, but I couldn’t stop watching this. When it finally got up to the modern era, I was sad they had run out of history.