While I'm sure you will get several different answers to this question, I want to encourage you to also answer it for yourself. I know it is often helpful to hear other examples to get started, but from the sound of the question, I'm going to assume that your teacher wants to hear your personal thoughts. This is a great exercise in self-reflection and should be fairly easy to write if you keep it as personal as possible.
That said, even though I am married with two children and have held a various positions within a couple of career choices, I do not personally like change. In fact, I completely understand (as of recently) why "moving" is considered by some lists to be more stressful than divorce and death in the family. I was the kind of person who, when there was no seating chart, would sit in the same seat every single day in class and actually get annoyed or even angry if someone took it before I got there. I like to have a schedule for my days and a general routine for my weeks. When I am in a set routine and my "life rhythms" are consistent, I find that I sleep better at night, am generally more pleasant during the day, and am overall healthier.
Now that I am the mother of two children under 5, I see where a routine has also made my life as a parent much easier. My husband recently went in to business for himself and we moved an hour and a half west in our state. I have been out of sorts for about 4 months as I still do not feel settled in my new house, my new neighborhood, and our new life purpose. It is unsettling, stressful, tiresome, to say the least.
I suppose when positive and controlled change happens in my life (such as the plan to have baby #2) it has been equally inspiring as stressful. I also tend to believe, on the whole, that change most often results in something better. But I'm willing to admit that it is particularly difficult for me when in the midst of it.
Of course, we cannot write this essay for you, but perhaps we can give you some suggestions that will be of help.
I would suggest that you write from your own experience. You should look at changes that have happened in your own life and talk about which ones you have liked and which ones you have not. Perhaps that can help you understand your own feelings about change.
All change, in my opinion, is stressful. We get comfortable with the way we are and we do not like having to adjust. However, there are some adjustments that are a joy to make (even as they bring stress). For people my age, major changes occur as we have kids and they grow. For someone your age, it might be the increased freedom that comes as you get older.
At any rate, your essay will be best if you write about things that have meaning to you, personally.