容嬷嬷投胎变成了老班
[róng mā mā tóu tāi biàn chéng le lăo bān]
Refers to a popular Chinese TV series “Empresses in the Palace”, with 'Lady Rong' (a strict maid of the empress) reincarnating as a stern teacher (headteacher or class advisor). This implies an authoritative personality who's hard on people but might have a good motive behind it.