PBL and the principal training

The principal training is playing a more and more important role during the principal's professional development,but we can't offer the efficiency principal training,under the existing system,how to raise the principal training substantial results is becoming a problem needing to solve urgently,PBL(the problem-based learning)is a kind of teaching model which concern problem solving,ability training and participating in nature,it would have certain reference meanings to the innovation of principal training to our country.