Riot at Xavier's
(from New X-Men (vol.1) #134-138, 2001). Quire makes his debut in Morrison's New X-Men #134 - Kid Ω and is the central character in the story of the riot. This is his origin story and still his most notorious defining moment.
After having a small but central role in Phoenix: Endsong, Quire returns as a main antagonist for the 2011 story arc Schism, his role in which would redefine the political landscape for the X-men and mutants in general.
Wolverine & the X-Men (vol.1) #1-3. Following the events of Schism, this is the arc that starts to redefine Quire as a more sympathetic character.
This 5 issue mini (by Brian Wood) is sort of both a return to form and a last great prank (gone horribly wrong, of course) and really helps illustrate the change that Quire starts to go through.
A+X #4 - Captain America + Quentin Quire - The New Deal?! Wolverine makes Quire team up with Cap' and it actually ends up being kind of amazing, as Cap' seems to get Quire on a level that no one would expect.
Wolverine & the X-Men #27-28 - Savage Learning (Parts 3 and 4). This is Quire's real test to become an X-man and is ultimately gratifying in that regard. Without reading the rest of the series, the end of this story might feel like it comes out of nowhere, but it's really sort of what Aaron had been building up to the whole time. Though polarizing among fans, Aaron's run really finds it's focus when Quire is at the center of it