"Cheap and easily spread."
Scott: "Hey Phil, have you seen the new girl Tracy?"
Phil: "Yeah Scott, but I hear she's got real margarine legs!"
A term commonly used to describe students at Christchurch Girls' High School, it is a play on words, meaning that girl's high girls are easy - margarine is easy to spread, as (apparently) are girl's high girls's legs
Boy from CBHS: Damn, where's she from? She's hot! And I think she's looking at me...
Girl from AGHS: Ah, CGHS. Why do they always steal our guys?
Boy 2: Um, cos they're hotter than you?
Girl from AGHS: No, because they're margarine legs, that's why!