I like Alphaghetti suggestion to clear the air ... tell her you've waited for everyone to have time to reflect on last week but feel it needs to be discussed and a plan put in place so it does not happen again - what does she need from YOU and than you tell her what you need from her and move forward if possible or terminate depending on how it goes - and I personally would make it clear that being YELLLED AT in future will result in immediate termination! We are role models to children on proper conflict resolution skills we need to lead by example