Starting at the top, is the helmet. Complete with face cage. The mandatory mouth guard is attached to the face cage unless the player has chewed on it enough and it is no longer attached. In this case, the light blue at the bottom of the face cage is Kidlet Three's mouth guard.
Shin pads. They protect the lower leg and knee.
Hockey socks are pulled up and over the shin pads. They are attached to the "jock" that is worn under the breezers. You don't want your socks falling down in the game. Hockey skates are next.