I was on the PTO board (from historian to president) for many years when my boys were in elementary school. It started out very disorganized, but over the years, we got things in pretty good shape. Had a mission statement, by-laws and everything!
And you could only stay in one position for 2 years, so we had a lot of different people helping out. I stayed away from it during middle school and with high school, I do their annual calendar project, but stay away from anything else.
Booster clubs are also very disorganized! I was on the track & field one last year and it drove me nuts during the meetings.
One thing that has really helped with all those organizations and getting people to volunteer is the online signup websites - signupgenious.com and mysignup.com - so much easier!