It sounds like your daughter is having a very difficult time separating. That's not unusual in 4-year-olds, but the severity of her behavior is. I wonder what she is like 10 minutes after you leave? Most kids with separation anxiety are fine just a few minutes after the separation is over. The normal approach is to drop off as quickly as possible. No drawn out goodbyes and no staying in the classroom for the morning. Give a quick kiss and ignore all of the tantrum behavior. There might be a couple of minutes of drama in the morning every day, but it ends quickly. Ideally, the teachers would distract her by getting her into a favorite or new activity right away. Alternatively, they could ignore her for the few minutes it takes for her to settle in. A simple reward system for entering safely could put some incentive behind making the transition without physical aggression.
However, these strategies sound like they may not be effective in this case. She has had over a year of practice making the separation difficult for everyone around her. She has learned (subconsciously) how to manipulate the situation so that all of the adults give their attention to her plight, and she's already succeeded in escaping from 3 other classrooms. In her mind, it's only time before she manages to escape from this one. Furthermore, her dangerous behavior toward the teacher cannot be ignored and may be too much for the teacher to handle.
Another option is to take her out of preschool for a few months and try again, preferably at a new place. She's a little too old for this, especially with kindergarten coming in September, but it does work for some younger kids who are just not ready for school. Sometimes it is easier for kids to transition when Mommy is not the one dropping off. Daddy or even a family friend may be easier to separate from. If none of these options work, I would recommend that you consult a child behavior therapist in your community. Behavior therapists (who can be psychologists, social workers, or others) experienced with young children are trained to fully evaluate separation anxiety and collaborate with you to make an appropriate behavior plan.
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