I really don't know whether to keep my mouth shut or to speak to Management about the following situation: A colleague teaches my (lively Reception) class PPA half an hour a week. I plan it, whatever I give her she cannot cope with, at first it was group work, really easy phonics but she didn't know her sounds, so I gave her bums on seats handwriting and they completely take the **** and do **** work. They don't listen to her at all. She has only tried to control them once - last week. She lets my TA classroom manage rather than do it herself - I have asked her to step back to see if the Teacher will take control, she doesn't. I make sure I'm out of the room so that the Teacher can attempt to establish control. I've given step-by-step instructions, put behaviour policies on the wall for her. I get everything ready and the children in place, etc. She doesn't seem to care and she will be teaching the class next year, she wants them split up and is publicly saying that she doesn't want certain children. I don't feel good about this and I don't want to have to speak to Managment, but I am deeply concerned. Any thoughts or constructive advice would be gratefully received. I remember when I was an NQT my colleague would tell me outright how to improve, so I've been the 'weaker' teacher. What do I do?