Still so much fear

Sarah has been home over 3 years now. She seemed to be doing much better, but then she started school. Now she has so much fear it is crippeling her. I met her teacher today. Her teacher says she is a smart girl. she does all her homework. she is very good in math. BUT..
I knew what would be said before she said it. She breaks down in uncontrolable tears when you critizes her in any small way. I mean small way. For example, Sarah please take the gum out of your mouth...followed by an hour of tears. I knew it was happening. She acts like she will be beaten with a whip if she doesn't finish her homework...and finish it perfectly. She acts like every piece of homework is an SAT exam. The weight of fear is too heavey to bear. Believe me, we are not perfectionist around here. This is an anxiety she carried with her from China. I'm looking into play therapy. Has anyone tried it with their kids? She is falling apart at school. It is really disrupting, and she needs to get past this fear.