A robin keeps flinging itself at a school window, and the students who gather around it see only a joke. They swear at it, laugh, and make threats on the bird's behalf. The jocks turn it into a bit of entertainment, and as soon as the library opens, everyone drifts away to their seats and newspapers.
Only one girl, outsider in her thrift-store clothes, stays behind. She sees what the others miss: the robin isn't trying to get in. It is fighting its own reflection, which she calls "that fat thing / that mocks his every move," and it wants that rival out in the open. Her reading is quiet and strangely tender.
The mood begins loud and rowdy, then turns reflective. The title hints at the link between the girl and the bird. Both are on the outside, and she alone grasps what the bird is really doing. The poem lets her insight stand without comment.