The first time you can get it is in the Quest "Loser to the Rescue". When Lindsey runs into you in the Gym have Isabelle stay with her while you get the Nurse from her office. When you enter the room Interact with the curtain and choose to pull it back and then tell her to "Smile for the camera!" or you could choose "Huh! It looks exactly like you were having a very wet daydream about the English teacher!" then "Just one for the yearbook, okay?".
The second chance is during the Quest "Photogenic" which you start by drinking a bottle of strawberry juice then going upstairs to the First Hall. No matter what you choose you will wind up outside the Nurse's Office and encounter the same scenario as your first opportunity.