There is a box of photos of the DA.
They begin at it’s first meeting in the Hog’s Head, with Harry looking regal as he explains its purpose, Hermione watching Harry as if to see if he’ll say her words, or his own, and Ron glaring daggers at anyone who looks about to say something rude in the face of the stoic child soldier talking.
There are photos of meetings, with Neville falling backwards onto pillows, Luna delighted over her first patronus, Harry looking at his students’ progress and looking older than a fifteen year old has any right to.
There are photos of the six DA students in the hospital wing after their night in the Department of Mysteries, beat up and bloody, Ron and Neville hosting new scars, Hermione journaling frantically and trying to figure out what it all means, Ginny’s hand on Harry’s back as he mourns Sirius.
There are photos of Neville’s recommencement speech, rousing students from all four houses and telling them the importance of defending themselves, photos of Luna sitting with a group of second years and explaining why they aren’t learning this in class anymore, photos of Ginny demonstrating a Shield Charm so perfect it sparkles in the stale air of the Room of Requirement.
There are photos documenting student injuries, tiny cursive underneath explaining the circumstance of every Crutiatus Curse.
There are photos of fourth year Hufflepuffs perfecting the Sectrumsempra curse on a Room of Requirement dummy, looking angry but proud.
There are photos of the Battle itself, of Death Eaters falling and students sobbing against walls, of teachers rallying their students like troops and siblings choosing sides.
The photos stop with one of Antonin Dolhov, with green light shooting towards the boy holding the camera.
Neville keeps all of Colin’s photos in his office. On the days where he wonders why he’s teaching at all, he pulls them out to watch the student’s side of the Second Wizarding War.
And he remembers.