The map is described as “awarding the world its world” because people in the outside world are the ones who have the opportunities. These children are limited to the slum.
Consider the next line after this phrase.
And yet, for these
Children, these windows, not this world, are world
By saying that these windows are their world, the speaker reminds us that the children do not have the opportunities that that map represents. This is why he says that the map is “a bad example/
With ships and sun and love tempting them to steal” (lines 17-18). Their world is so limited that they can only hope to see the rest of the world through a life of crime.