Possibly having an unpleasant experience at school either with another child or the teacher triggered your child's change of heart about going to school.
Talk with your child. Ask direct questions about why she does not like to go school. Let her draw a picture about it, as it might be an easier way for her to express her feelings. Also, it might aid you in understanding her feelings.
Talk with the teacher. He or she might be able to give you an insight about what is going on with your child at school.
this year we moved and my daughter loved the new school and her teacher after about a month she didn't want to get up for school and it was a battle everyday this went on for a few weeks and I would ask her why what was the matter she would always tell me I miss you when Im at school would break my heart to have to make her go.Then one day we was shopping and she ask to have this book bag it was the kind that goes over your neck and the next day she got up the first time I went to her room and we haven't had a problem since she still hasn't told me if someone made fun of her first back pack or maybe she wasn't comfortable so maybe someone has made fun of your child or he or she needs a self-esteem boost.