A Supplement to the act of March 10, 1949 (P. L. 30), entitled "Public School Code of 1949," establishing rights in public school employes to organize and bargain collectively through selected representatives; providing compulsory mediation and fact-finding for collective bargaining impasses; defining the scope of collective bargaining; establishing unfair employe and employer practices; permitting strikes under limited conditions; providing penalties for violations; and establishing procedures for implementation.