B.W.
This is a very common phase, it bridges the gap between when a child begans to understand what he/she wants to express but does not yet have the words and so uses actions. Please becareful on how you use the word "bad" around your child. If it is used to often or in the wrong way, it can create a feeling of worthlessness in a child. Example: "You are bad", Vs. " What you did, or your actions are bad". The first one can lead to self-esteem issues the second can help your child learn which actions are acceptable and which are not. Instead of using the word "bad" though I explain to my 3 yr old what consequences are and that every action has a consequence. I started this when he was about the age of your daughter and now he is able to talk to me in more detail about consequences and ask me what the consequence of a given action will be. This helps him decide if an action is worth prusuing given the consequences. Your child is going to pick up all kinds of behaviors and words and ways of coping at daycare, some may be helpful, others you will wish she had not learned. I try to model the behaviors I want my child to learn and explain to him why other behaviors are less desirable. For example: "If you bite your firends they will not want to play with you" Simple cause and effect to us but a new concept to our children and one that your daughter will pick up on. Start trying time outs and talking to your daughter. Biting a child when she/he bites you only teaches your child that it is ok to do thoes things to others who are smaller and more helpless than you. That is not a message I want my child to learn. Hopefully the teacher in your child's daycare class will be willing to work with you to help stop this behavior.
Good luck!!
B.