- "'Brown, Lavender' became the first new Gryffindor and the table on the far left exploded with cheers; Harry could see Ron's twin brothers catcalling."
- —Lavender is sorted[src]
Sometime that autumn, she befriended a girl named Parvati Patil, a girl who shared a dormitory with her and went to the same classes.
That Hallowe'en, after a lesson on Wingardium Leviosa in Charms, her friend Parvati Patil told her that Hermione Granger, a girl in their dormatory, was crying in the girls' toilets and wanted to be left alone; their conversation was overheard by Ron Weasley and Harry Potter.
Lavender returned to Hogwarts this year, having passed her first-year examinations. During a particularly boring History of Magic class on the International Warlock Convention of 1289, she fell asleep but was woken by Hermione Granger asking Professor Binns about the Chamber of Secrets.
In her third year, Lavender and Parvati began taking Divination, a class which taught how to see the future. In the first lesson, she was addressed by Professor Trelawney and was initially frightened, although she was relieved to learn she was only wanted to pass the teacher a large silver teapot. Upon doing so, Professor Trelawney told her that the thing she was dreading would happen on Friday, 16 October; Lavender began trembling at this.
Later on in the lesson, Harry Potter was told his tea-leaf omen was that of the Grim, a large spectral dog that haunted graveyards. Although she was at first confused and looked puzzled, when Professor Trelawney revealed that the Grim was the symbol of death Lavender "clapped her hands to her mouth" in horror.
After the class was dismissed, Professor McGonagall reassured everyone that Divination was "one of the most imprecise branches of magic", and although most of the class relaxed, Lavender remembered that Professor Trelawney's prediction about Neville Longbottom's cup breaking came true, and still worried.
After lunch, the class had their first Care of Magical Creatures lesson with Professor Hagrid; Lavender was the first one to see the Hippogriffs they would be learning about; upon seeing them she was said to have squealed, pointing to the opposite side of the paddock. Harry was chosen to pet one first, and Lavender reminded him fearfully of his tea leaves; he ignored her.
During the Defence Against the Dark Arts class with Professor Lupin, she screamed upon seeing Ron Weasley's spider-boggart, and ran to get out of its way; she was one of the few who noticed Lupin's boggart, which she mistook for a crystal ball.
She and Parvati Patil took to haunting Professor Trelawney's tower at lunch-time, and came back with annoyingly superior looks on their faces, as though they knew things the others didn't; they also took to using hushed voices when speaking to Harry, as though he was dying.
Later, on 16 October, Lavender received a letter from her parents saying her rabbit Binky had been killed by a fox. She cried about it while in line for Transfiguration class, but seemed to be calm enough to speak to Hermione Granger; the two conversed for a short amount of time, because Hermione's seeming lack of interest in Lavender's feelings brought Ron to vehemently remark about how Hermione didn't care about other peoples' pets, but perhaps luckily Professor McGonagall let them into the class at that moment.
- Harry Potter and the Philosopher's Stone
- Harry Potter and the Chamber of Secrets
- Harry Potter and the Prisoner of Azkaban
- Harry Potter and the Goblet of Fire
- Harry Potter and the Order of the Phoenix
- Harry Potter and the Half-Blood Prince
- Harry Potter and the Deathly Hallows