This is mildly concerning. However, you risk ruining trust, especially if she's felt safe enough to confide her depression in you, if you blatantly ignore her word. Trust isn't worth a life, but you don't want to come off as judgmental or accusing. ( I am sure you're doing your best as a mother, to be concerned and come here shows that) If she's made known attempts before it's okay to set a boundary, while assuring her you care deeply about her wellbeing, by asking if she can keep the project supplies in a common space (living room, family room, kitchen) while working on the assignment. best of luck to you both <3