Cannonball

In this room, go to the left on the first beam. Use your clawshot to kill the bats and knock down the ice thugs. When you reach the end of the beam, jump across to the beam on the right. There are two chests, containing a red rupee and compass. Aim the clawshot at the target next to the door to get access there. Head back through the window as wolf Link and you will be back in the courtyard.

Use your senses and you will find a digging spot. Go nuts digging this spot and you will find a chest containing a small key.

Use the key to unlock the door on the side. There is a hallway with three cannonballs that will prove to be useful. Pull the handle next to the door and place a cannonball in the holder. Go through the door and pull the handle on the other side so the cannonball comes to you. Carry the cannonball over to the cannon and rotate it so that it faces the opposite direction. Blow up the ice beast blocking the door and go through the door for a session.