Following up on the story of a 9-year-old on Staten Island who was sent to the principal’s office after playing with a two-inch plastic toy gun, the Daily News tells us today about a 12-year-old girl who was arrested for writing on her desk in erasable marker. In lime-green, she scrawled “I love my friends Abby and Faith,” signed her name “Lex was here. 2/1/10,” and drew a smiley face. We understand the teacher’s irritation with the last part: The blasted smiley face is like a pepper shaker to the eyeballs for middle-school teachers. But an arrest? Seems a little extreme. Had she drawn one of those diamond figure-eight symbols, or even worse, a smiley face with the tongue hanging out, then maybe we’d understand.