It quite upset me to hear this shouted. They are year 3/4 mixed class and some are barely 7. If your child's teacher shouted "go away" quite meanly at them would you be upset? The tone was really quite spiteful and it was like she had no time for them. Plus some of them are not getting on with their work as they don't understand and are too scared to ask her again.
What would best course of action be bearing in mind this teacher is deputy head.