Part of the reasoning for playgrounds being built was to ensure that children are exhausted by the end of the day and will go to sleep at nighttime. Children have plenty of energy and by taking them to these playgrounds that function almost as training camps, we prepare them to integrate into real life. It is a place where the world still remains in order. It is an idyllic and safe location for those people still pure and innocent like children.

The playground in front of a school
The playground in front of a school · The Birds · Alfred Hitchcock · 1963

Movies often use the location playground for symbolizing contrasts. What follows a scene on a playground is often radical and shocking, especially when used in the science fiction genre. In “Fahrenheit 451” 1966 there is ultimately a raid for books even at the playground, as not even children are allowed to possess any. And just before the Pre-Crime unit raids the apartment in “Minority Report” 2002 the playground in front of the housing block reflects an obscure normality. The most extreme example is given in the opening sequence of Terminator 2” 1991. As humanity has already been wiped out in the second scene of the film by a nuclear war, we witness burning playground equipment. Later in the film we see the events leading up to this event. The protagonist witnesses in her dreams how a peaceful scene of mothers and children at the playground turns disastrous as the nuclear mushroom clouds wipes out everything. It is this image that gets burned into her mind and also into the heads of the audience, and it is this image that is the driving force and her motivation at the turn of the film. Another variant of the possible contrasts are the characters or subjects that occupy a playground. The breakthrough of horror in The Birds 1963 is delivered by a playground scene. The protagonist is waiting in front of a school to pick up a child. A plain but large climbing frame is not within her vision, so at first she at cannot detect the birds that are slowly but steadily gathering there. 

The presence of gangsters, drug users and other antisocial characters desecrate the innocence of the playground location. In “Welcome to Collinwood” 2002 the degenerated and shabby surroundings portray that innocence has long since been lost here.

Besides children and their supervisors only two groups of people are legitimately to be seen on playgrounds: adolescents and pensioners that have long outgrown their playful periods. They come to find closure or to say goodbye, like in “Fickende Fische” 2002. The older ones return to search for something, or at least a memory of their past, “About Schmidt” 2002.

A single camera shot of a playground by Roman Polanski in “Carnage” 2011 is enough to symbolise the basic conflict of the entire film. A group of ten and eleven year olds bully a boy, who defends himself with a wooden pole, as if to say that not even playgrounds are the innocent and idyllic places we think they are.