When you act a differentway at school then how your really feel. You tend to hide your true emotions. You could also tend to not be yourself just so you can fit in.
Karen has such a school act on you can obviously tell she is sad.
Well It Means You're Turning The Other Eye Against The Situation At Hand Or On Sight With That In Regard You Act Blind As If You Didn't See Nothing Cause What You Saw Is Pretty Much Hilarious