Bandura: Procedure - 36 male kids and 36 female kids (3-5 years old); participants put in a room with model, a bobo doll, hammer and other toys; aggressive model shouts and attacks bobo doll; non-aggressive model sits passively and does nothing with doll; after 10 mins, ppts kept in separate room with no toys for 2 mins (aggression arousal stage); ppts then left in a room with toys for 20 mins and observed