I almost always include some balance work in the strength segment of my aerobics classes. I try to combine standing on one leg with some one-handed strength moves to create instability, because if I do balance alone the students will get bored because it doesn't "hurt." Hopefully some of them will have read this... maybe I should print it out.

I still wrap my bad ankle when I'm doing a lot of lateral movement, like aerobics, or when I know I'm going to be walking on unstable surfaces, but I haven't sprained it in, oh, at least five years (touch wood).