The episode title is an excerpt from a quote from George Eliot's novel 'Middlemarch' - "Signs are small measurable things, but interpretations are illimitable, and in girls of sweet, ardent nature, every sign is apt to conjure up wonder, hope, belief, vast as a sky, and colored by a thimbleful of matter in the shape of knowledge..."
The new character of Cole is introduced in this episode, and the school kids pretend he has always been at the school when we know he hasn't!