Once considered too easy, is teacher certification now too hard?

http://michiganradio.org/post/once-considered-too-easy-teacher-certification-now-too-hard#stream/0
For years we've had tests for teachers that miss the mark, often by focusing on content but not the specialized skills needed to teach it. Deborah Ball appears on this Michigan Public Radio story to discuss the current state of teacher preparation and testing and the directions we're heading.