How to address myself?

My Name is Kavitha Reddy, married. I am working as a pre-school teacher. People address me Mrs Reddy and sometimes Ms Kavitha. My question is when I am introducing my self to parents, other senior teacher and board members( formal) and kids.....How to introduce my self. Can I say," Hello I am Mrs Reddy or Miss Kavitha" or should I introduce my self" Hello, I am Kavitha Reddy or Kavitha".
1.Can I use Miss or Mrs when introducing myself?
2.If i say Miss Kavitha, does that mean I am unmarried?
3.what is proper way of introducing myself formal and semiformal and informal?