What best describes the place where the sidewalk ends?

While many of the poems reflect—at least thematically—real world situations and possibilities, a recurring theme is the possibility of the fantastical. A character named Jimmy Jet, for instances, watches so much TV that he literally turns into a television set. Sarah Cynthia Sylvia Stout’s stubborn refusal to obey her father’s orders to take out the garbage eventually results in that garbage reaching to the sky and stretching from coast to coast. A little girl who doesn’t believe her friend’s claim that his pencil has a magic eraser pays the penalty for her doubt by being erased from existence herself.