Lawrenceville is around 30% day students, but the Saturday classes keep us (and really everyone—we’re not one of those schools with “dead weekends”) on campus.
Do look into size, though; Lawrenceville is around twice as large as Mburg, so the way each school fosters community is very different. I think that Lawrenceville does surprisingly well at encouraging class unity (especially freshman and senior year, where most students live together and eat in separate dining halls), but the vibe of a 120-person graduating class is still nothing like that of a 220-person class.
Case in point: We were recently having school president elections, and there was one person who everyone thought was going to make it to the runoff round because pretty much everyone in three different houses supported her. When I was told about this person’s popularity, my only response was “who?”