I've always kept myself to myself. I've worked in a total of 5 schools. I've always completed contracts and I've stayed in some schools for more than a year. I've been in my current job for 4 years now, and it's by far the best job I have had. The reason? I'm left alone.
In previous jobs I noticed a trend - the better you are at your job, the more that's expected of you. Now, that's fine if there are rewards or you feel appreciated, but when the schools you work in keep giving jobs out to anyone, and you have to constantly clean up their mess, you soon learn to concentrate more on your job, and you stop worrying about trying to impress and do favours.
My school knows I'm always willing to help and do favours, but they also know that everyone has their responsibilities. My responsibility as a homeroom teacher is to take care of my kids before all else. It's what the parents pay for and it's what I signed up to do.