The cafeteria is, actually, not worse than a lot of school cafeterias. It has scruffy floor tiles, long tables, solid-looking walls, a moderately high ceiling with beams and ventilation grates which the smart kids are standing clear of, the food line (currently closed, it's after lunch and not yet dinner) against one wall, the tray busing rotating with ominous clacking in a corner. The older students are all there, to guard the new freshmen and get them water and collect their care packages from them. There are some tearful sibling reunions. There are some more-tearful instances of younger children shouting a name the older ones don't recognize. 

Some of the more diligent and organized upperclassmen are handing out paper cups of water to every shell-shocked freshman as they wander in, and herding them to the center so there'll be space for the rest of them.