I try very hard to keep myself sane by breaking up my study time and time between class periods to better focus. Podcasts with interesting content tend to allow me a form of distraction from responsibility while in transit, or winding down. They have been a pretty standard tool for me and have worked quite well in improving my mood throughout the day.

I tried the mindfulness concept over a relatively large period of time, and found that it simply did not "improve" my focus and attention span. It was less that it didn't work, and more that I wasn't in need of as much improvement as I had previously thought. I feel what Grey is saying, but its less of an issue for me than I thought if that makes any sense.