I find reading a good way to improve mine. I read allot of magizines and a few books every month.I enjoy what I read so find something that you like to read before doing so.
I have beenb pondering the same question. When I do math, I get zoned in and my concentration does not break unless I get frustrated or the problem is too easy. I find doing those problems of medium difficultly work the best... they also increase your intelligence. Another thing I do is when I am walking around outside my apartment, I see people walking around all the time.. I try to concentrate as hard as I can on what sorts of patterns I can find.