That’s the same bag Maida had in the scenes where she’s fleeing Mars. Have you ever had bags and suitcases that stay with you over multiple big transitions? I have.

↓ Transcript
Panel 1: Maida quietly closes the door of the head teacher's office.
Panel 2: She walks down the hallway. There are a few other students around, but no one that she knows.
Panel 3: She gets to her locker as her ID card buzzes to get her attention.
Panel 4: Zaynab (on text): "Well?"
Panel 5: Maida (on text): "It's bad. I'm clearing out my locker." Zaynab (on text): "Oh, Maida! Noo!!"
Panel 6: Maida closes the ID card and exhales loudly as she leans against her locker for support.
Panel 7: She gets out her shoulder bag, the same one she's had since Mars.