A MA elementary school is selling ad space on the backs of permission slips and notices sent home to parents. It’s better than another bake sale, say officials, who have pledged to keep the advertising appropriate for families. No ads for alcohol, tobacco, political causes or tattoo parlors will be allowed. Is this any different than ads in the back of yearbooks? Or one more tumble down the slippery slope of commercial encroachment in our public schools? Take our poll and sound off in the comments.