This October I started in a new school as an SLT. Things have been fine, but on Friday another member of staff undermined me in front of the school. Basically I asked some children from her class to do something in my assembly, but as this teacher was in a foul mood, she refused to allow them to do it and told them it didn't matter what I had said, she said no!! I was really taken a back as I haven't seen this side of her before (others have, but I hadn't) and didn'treally know how to handle it. I've been thinking about it all weekend and although I hate confrontation, I feel I should challenge her for undermining me as a colleague and as a member of SLT. I know she is volatile, but if I don't make a stand I could have more problems in the future. What do you think?