Tish is writing journal entries as an assignment for her English teacher, Mrs. Dunphrey. She has promised not to read any entries marked "Don't read this" and that is exactly what Tish writes before almost every entry. As Tish struggles with her abusive father and neglectful mother, she writes about those struggles in the journal. Dunphrey comments positively about how much she is writing, asks her to write some entries she can actually read, and also scolds her for not turning her journal in on time and for not completing other homework assignments.
The contrast between Mrs. Dunphrey's admonishments about homework and Tish's struggle to survive is heartbreaking - how can Tish reach her potential when, unbeknownst to Mrs. Dunphrey, she is struggling just to survive another day?