I like the way you think!
Heh! Me and my Buds did that to our English Teacher in the 8th grade! Problem was, we laughed so hard after her little poodle tramped around in it and tracked it all over her carpet, she knew who we were!
I got an "F" that semester! Did I mention her carpet was a white Persian rug? Hahahahahahahahahahahahaha!!! Ah the memories of childhood!
ETA:
Oh yeah, she was one of those unmarried "old maids", and looked the part!