We talk constantly about director burnout, but teacher burnout over severe child behavior is currently an absolute epidemic in our industry. When a lead teacher is spending eight hours a day managing explosive tantrums or keeping classmates safe from aggressive behavior, they eventually hit a physical and emotional wall.
You absolutely cannot blame the teacher for struggling. When a staff member comes to you in tears over a difficult child, you have to physically step in. Tell them to go sit in your quiet office for twenty minutes while you take over their classroom. Show them that you are in the trenches with them, not just behind a desk handing out advice. Then, use your administrative power to get them real help. Bring in an outside behavioral specialist to observe the room, or implement a reduced schedule for the child in question while a support plan is developed. Teachers who feel genuinely protected by their director stay. Teachers who feel abandoned eventually quit, and replacing them will cost you far more than any behavioral intervention ever would.