Two Selves
We see Billy walking into Mrs. Wilkinson's class for the first time, and his image is reflected in a mirror. At this moment, we see two images of Billy, which together represent his uncertainty about what he wants in his life and whether he ought to be dancing. The mirror of the ballet classroom shows the psychic doubling that Billy has to go through in order to even start taking ballet—he knows he must act in one way with the men in his life, and keep his passion for dance a secret.
Boots
We see Billy's blue boxing boots amidst the white ballet shoes while he's in the class with all of the girls. The image helps us to to understand how much Billy stands out for choosing to dance—the fact that he is an outlier in his community, a boy choosing to do the typically girly thing.
Billy waving through the bus window
When he goes off to ballet school, Billy's older brother Tony walks towards the bus and mouths something to Billy just before the bus leaves. Billy cannot understand him and as the bus pulls away, he runs to the window and yells to Tony. The image shows that Billy is scared of leaving his home behind and facing the unknown, that he is sad to lose what little connection he has to his brother by going away to school.
Final Shot
The film ends with a fully-grown Billy leaping onto stage as his father and brother watch him perform as a professional ballet dancer in a production of Swan Lake. Billy's Dad gasps as he sees how incredible his son is in the ballet, and as the adult Billy reaches his highest height, we see an image of Billy as a boy, leaping jubilantly into the air, filled with a love for dance.
