but as with any discipline, a big part of how much fun it is to learn has to do with how it's taught.

I teach (technically still in college, but true enough) basically the opposite of you, history, and this is very true. You can make history lessons fun and engaging and challenging, but it's also very easy to make them boring. Unfortunately, as you are also aware of, it's difficult to make these interesting lessons with the constraints of time (of which administrative bullshit takes up a lot), class sizes and government-mandated curriculums and tests.

Last year I had my internship at a pretty shitty school with abysmal guidance and support which meant I was teaching all on my own even though I shouldn't have been allowed to, and basically no curriculum. That sucked, but it also meant I had basically total freedom in what and how I taught, and the classes were 12 students maximum. I pretty much only did engaging and fun lessons for 4 months straight.