Let's get started, then.
Go figure, the signs are still up. The insides of the school haven't been damaged quite as badly as I'd thought after all. Unfortunately, that's quite a bit more than I can say for the classrooms themselves, as being exposed to the hostile elements of the land outside through broken windows for several years has reduced their insides mostly to assorted piles of rubbish. The paint's been seared right off the walls, the lights are all broken leaving shards of glass all over the floor, most of the furniture looks like it was consumed by fire... Still, who knows, there just might be something here that I can use, or that'll jog my memory.
I get to work immediately, separating worthless, ruined and otherwise brittle materials from items that have fared better and endured the punishment of time. It doesn't look particularly promising so far. Most of the desks have been completely destroyed, leaving behind pieces of metal pipe that would probably sear my flesh again if I touched them directly. A couple of desks in the back of the room, away from the windows, have endured better. I decide to check out the desk drawers.
Again, there's not much. Remains of what probably used to be paper, the majority of it having combusted at some point or another. Surprisingly well-preserved pens and compasses and the like. One drawer actually has some manner of partially melted plastic gun-shaped device in it, which turns out to be a freaking taser of all things upon closer inspection. Doesn't work, obviously.
Who hides a taser in a school desk? Honestly.
I move back to the front of the classroom and check the teacher's desk, but aside from more burnt paper it seems to have been cleared out at some point. I do, however, find a rather well-preserved key, and pocket it just in case. The last thing that comes to mind is to check the blackboard for any sort of compartment behind it, but this room doesn't appear to have anything of the sort.
Oh well, moving right along to 101-B.
This one has a locked door, surprisingly enough, and the key I found doesn't fit the lock. I try kicking the door in, but the lock just won't break. I consider using my power, but decide to keep looking around first; maybe I'll find a key, and if not, I could always climb in through a window from the outside.
The door falls off its hinges when I try to open it, kicking up a dense cloud of dust into my face; I can't help but cough a little, but my vision is unimpaired by this. This room seems even harder hit than 101-A was, so I don't waste too much time searching through it. Practically everything that was ever in this room has been completely destroyed, although curiously enough some of the items seem to have been ruined intentionally, rather than by wear-and-tear caused by the hellish conditions the school's been engulfed in. A metal pipe that used to be the leg of a desk lies on the floor, one end of the otherwise round hollow pipe squeezed shut, as if someone bent it back and forth until it snapped off. Speaking of bent, it definitely looks like someone hit something or someone with this at some point. Regardless, the makeshift weapon was abandoned in the classroom, and there's no other clues to be found in this particular one.
Now we're getting somewhere. The desks in this room have survived far better than the others, which means less foraging around in a pile of refuse and more going through drawers. Some of the papers have managed to not get burned beyond recognition, although the majority of them are, surprise, school-related stuff, class notes and homework and such. I suppose expecting to find a convenient apocalyptic log or something was hoping for a bit much. I do find a bunch of girly accessories and whatnot, but barely anything useful. I pocket a few paper clips and other miscellaneous items you'd find lying around in any school, just in case.
Aside from being as well-preserved as the previous room, what immediately catches my eye is the blackboard at the front of the classroom, which has been smashed in half, as if something large either tackled it or was thrown into it. There also appears to be a knife embedded in the wall next to the board. It's stuck pretty good, and seems otherwise unremarkable, so I leave it be.
One of the desks has a porn magazine hidden in the drawer. I decide to loot it, since it could be a valuable clue.
More signs of fighting, improvised weapons, dents in the walls... What happened here? Did the school come under attack before the cataclysm hit? Is what happened in this building connected to what happened to the rest of the area?
Is whatever they were fighting still around here?
Well, that's unlikely. It's been years, and I can't imagine much besides myself would be able to survive in this hellhole. Even if it could, it wouldn't have anything to eat. Speaking of which, I find what looks to be the charred remains of what was once supposed to be a sandwich or something, in one of the drawers. It looks like it was left in a working toaster oven and just forgotten. What a waste.
Another locked door. The key still doesn't fit; it's probably for the staff room or some other room the students were never meant to have free access to. This door is a little less stubborn, though, and a well-aimed kick breaks the lock.
Ah. I was wondering when I'd find one of these.
A dessicated corpse in the corner, curled up in a loose fetal position. Most of its flesh has been eroded by the dust storm beating in from the windows, so its extremeties are missing digits and it's showing a lot of exposed bone. It's impossible to tell whether it's male or female, or even if it was originally human. A few scraps of seared cloth are all that remains of what clothing it once wore, and I can't find any belongings on it worth looting. A bent key lies on the floor near the door I broke through, suggesting this person locked themselves inside.
Why? To hide? To keep something out?
The rest of the room is practically empty, one of the rooms that has suffered the most damage from the hostile weather over the years.
The door's been split in two diagonally, both halves still attached to the hinges. The cut goes through the lock and penetrates the opposing door frame, making the door impossible to close. I find a mostly-burnt flyer advertising the school's kendo club in one of the drawers. Nothing else of note in this room.
The door wasn't locked, but was barricaded with a large ruler meant for the blackboard and a few desks and chairs. It didn't take me much to break through. Strangely enough, however, there's no bodies in this room, suggesting whoever barricaded the door probably escaped through the windows.
I loot a thin metal nail file from the room.
Well, that was quite a bust. All I managed to find was some paper clips, a nail file, a key I haven't found a use for yet, a bent compass, a magazine which I'm sure will be of use sometime later, and a flyer for the kendo club, plus assorted tiny screws and whatnot which I simply dumped into one of my pockets. No real clues, though, despite wasting a good hour or two sifting through garbage with my bare hands.
Suddenly, a ominous sense of danger washes over me. If you've ever walked in front of a car or something without noticing it, you know what this feels like. Not the shock once you turn and see it, but this subconscious sense of alarm bells going off just before that. It's coming from outside, a fair distance away, but it's definitely coming this way, whatever it is. I can't help but feel my heart rate quicken in anticipation of an unpleasant encounter. Could there really be anything else out there besides me.."
I reckon I've got time to check one more location before whatever it is gets too close for comfort, tops.
 I see stairs leading underground right past the entrance. Maybe some manner of basement wardrobe for the students, or something along those lines. It's dark down there.
 I see stairs leading up to the second floor. I'd assume there'd be more classrooms, maybe clubrooms, the teachers' lounge... The stairs don't look very stable, so it might be a one-way trip for the time being.
 I should check outside to see if I can find anything else of note. I did just rush inside as quickly as possible to escape the storm, so I didn't get to look around the territory much. The wind howls menacingly at me from behind the door I broke through.
 (Write-in option.)