Another brain teaser?

Question

A yong 6yr old girl lives on the 15 floor of a block of flats , every morning she gets the lift all the way down to the ground floor then makes her way to School.Coming home she gets the lift to the 6th floor then takes the stairs the rest of the way. Why?

Answer 1

she can't reach the fifteenth floor button

Answer 2

Because She Can Not Reach The 15th Floor Button

Answer 3

She can't reach the button.

Answer 4

"...but when its raining she takes the elevator up"

shes too short to reach the 15 button

but can reach it w/ the umbrella

Answer 5

She can't reach the button for the 15th floor.