Stepping over the classroom threshold, my body jolts to a halt. Like a hummingbird not seeing the sliding glass door, I am thrown up against an invisible barrier. Oddly, not one ten-year-old head turns to acknowledge my entrance.  Each young participant's eyes are locked on a particular student.  There are words being released into the air, but they do not reach my ears.  She is calling on individuals, but I am momentarily deaf.