The math I use is to figure out how much money i've already spent in the store, certain ratios, figuring out the multiples of 8 (because minecraft is based on them), and counting how much time I'll have to sleep if I say, stay up until 6 and set my clock for 10:30. Most of this stays in the realm of basic operations and hardly ever branches out beyond that (with exception to calculating exactly how much cobble I need to mine from my generator and how much of that needs to stay raw, turn into stairs, and be smelted so it can be crafted into bricks).
So, for me, Minecraft is usually the most advanced math I ever get into.
Also: I'm thinking about doing a paper on numbers/patterns in nature (one of the subjects we'll be glossing over in the class and was suggested in the official document about the requirements for the paper. Seems very interesting based on what Wikipedia has on it).