Well, for me at least.
I realized awhile ago that I use the school year to determine my "year". I suppose this makes sense, because the school year has dictated what I can and cannot do for the majority of my life. First, while I was being homeschooled. Then while I was at college. Then my husband was in grad school. And now, in just a few weeks, my husband will be teaching classes while finishing up his PhD.
I actually like this way of measuring the year. This cyclical view can be reassuring. The end of August and beginning of September is a natural starting point for new beginnings. May has both the great anticipation of a summer vacation and the satisfaction of completion. Summer is a time for catching up, preparing for the next year, and maybe even having a more relaxed schedule. (Of course the summer is still busy, but it is a different kind of busy.)
I embrace this difference in my husband's chosen profession from the "normal" Monday through Friday, 9-5, fifty weeks a year, two week vacation careers. I believe that it will give our life structure with a natural ebb and flow of work and fun. Somehow this feels more natural to me than the above "norm". It seems to me that man is supposed to have "circles" in his life. The world we live in is full of cycles: the days of the week, months, the seasons, the sun and moon, life and death. The list goes on . . .
(I can't talk about the Circle of Life without a Lion King reference, can I?)