Miniature commandos: Why do young children play aggressive games?

One of the most frequently heard complaints among caregivers is that young children insist on playing super hero or fighting games. Around the age of four, a perfectly sweet and wonderful group of children can transform into a miniature commando unit, arms and legs flying as they challenge anyone and everyone wandering into their territory. It's as predictable as puberty, and often just as frustrating for adults. 

• Super heroes - A Case Study http://www.hi.com.au/eec/super_case.htm
• Dramatic Play http://www.islandparent.ca/articles/dramatic.html
• POWER PLAY: The Good, the Bad and the Ugly http://www.preschooleducation.com/art20.shtml
• Raising Trouble: More Bad Guys  http://bitchmagazine.org/post/raising-trouble-more-bad-guys