Trampoline Size

11-yr-old viola student.  Wet hair.

Me: Is your hair wet because you've been swimming, or because you've been running around in the rain?
Girl: Um... I was jumping on the trampoline.  With my friend.  In the rain.  [Grinning]  It was fun.
[Later] We were jumping with washing detergent on the trampoline.
Me [not exactly sure what she meant]: Could you explain that one?
Girl: There was a trampoline.  It had washing detergent on it.  And it was raining.  We were jumping.  It was slippery...  Oh, and the trampoline is puny.  Like, the same size as that table.  ... Oh... wait... No, it's a bit bigger.  Like, maybe 4 times bigger. [Starting to giggle uncontrollably] Or even 5 times bigger.
Me: Mm, good size estimation there.

I did point out (while she recovered from that batch of giggles) that I was glad she had survived with no injured extremities or trips to the hospital.