On CBC’s Spark the other day Nora Young interviewed David Plotz, the editor of Slate.  He

Got into my running gear this morning with a plan. Walked my kid to school and ran into the moms in the schoolyard. I’ve always had this secret feeling there’s a mom gang that I’m not part of, and while they are always friendly when I walk up, I suspect they have mom-gang plans they wait until I've left to execute.