What is She Doing?

Saw something quite interesting as i was about to drive away from a car park in jurong west. i was looking around and i saw this from my side mirror
On a closer look, i saw a group of teenage girls at the first storey of the flat, right below the kitchen window, and this other girl was talking to them standing at the window. i couldn't hear them but they seem to be trying to do something and not just talking. thn i saw the girl went into the flat and back with an umbrella, she brought the umbrella out of the window and hun it by the bamboo pole. and the rest of the girls were pointing at the big water pipes belos the window sill...hhmmm i really hope she wasn't trying to slip out of the house by climbing out from there!! it would be disastrous if she spil and fall. After watching for a while.. they decided to give up .. i think the girl didn't have the courage to climb out.. which was a good thing.. i think they were at most 14 yr olds... and the way they talk and their mannerism.. ah lians in the making!!