In the courtyard where Dean is standing.
The spiral staircase when you walk up to DADA.
In the Viaduct.
The fourth floor outside in the balcony.
In the Paved Courtyard. You must repair the broken staircase in the corner. It 
is at the end of the balcony in the corner.
Note: You can use Incendio on Talking Gargoyles for Discovery Points.