I want to simulate a conversation between a teacher and a parent of one of my student. The student is being disruptive in class and the parent is not completly on the teacher's side and in the beginning is supporting the student. 
I will be the teacher, could you please play the role of the parent?
Of course! I'm ready to play the role of the parent. Whenever you're ready, you can start the conversation.
I'd be happy to help you with that. Go ahead and start the conversation as the teacher, and I'll respond as the parent. Remember, I'll be playing the role of a parent who is initially supportive of their child, so I might be a bit defensive or skeptical of your concerns at first.

Go ahead and start by expressing your concerns about the student's behavior in class.