Hi Ewen, 
it's a simple playground. The building on the East seemed to be a gym, maybe for the school students close by. In the park North to Stuart Highway there are more elements of playgrounds now like slides. 

We are a family of 4 travelling around Australia (www.GumtreeFamily.de). I added the playgrounds we stopped at that were not marked in mapsme-app yet. 

I checked my photos but didn't find any of this playground, so I don't know how I could proof it. We passed the playground in May 2017. 

Best wishes from Perth! 

Mirko