This was posted to a local railfan forum recently by a friend of the driver. To answer a few of the questions here, it was a light engine movement here in Melbourne, Australia. Being a single locomotive with no wagons it pulled up quickly. The driver was taping his run to show some other railfans a drivers eye view of his day. There are used to be a lot of Australian cab view videos on youtube until a couple of railway companies began hassling youtube into taking them down for "security" reasons.
As for what the kids were doing there, there was wet paint on the bridge and empty spray cans lying around, what do you think they were doing?

My wife's grandmother taught her budgie to say his address years ago, in case he ever got out. She also taught him to barrack for her favourite football team, who were named after the suburb they started in. The bird would swap the suburb names randomly, and of course there was a street of that name in both suburbs.
Fortunately, he never got out so no one ever had to figure out where the bird came from.