Figured out how to install a ton of games on school laptops. School was pissed that I was running a Minecraft server

Made a basic script with a nested loop to burn ~20 mins before playing some annoying sounds using the PC speaker. The PC must have been a <=286. I started the script once just before the English teacher arrived and disconnected and hid the keyboard. It resulted in some entertainment when he had to try to silence the PC, but eventually he found the power button.

While not technically a school computer. In college we all had to install a WiFi client to access the school's WiFi. It was shit so I started digging around and found the localization files in plain txt. I then, when I had the opportunity to, booted into a friend's computer with Linux and changed the confirm button to say "I'm a bitch". They never asked me to change it, which I would've, so it just stayed like that all year.

I once switched the psu from 220 to 110 volts... while it was on

Our network had a program called "deep freeze" on every computer that was basically an automatic system restore point.

A friend worked for IT during the summer and got the password to turn it off. I could make any change I wanted and make it 'permanent'. I didn't do this much. My favorite hobby was opening word docs that students saved on shared drives and replacing the word "the" with profanity.

In high school, my friends and I were getting into Ubuntu. We were smug Linux nerds. We came up with the idea of installing Linux on one of the school computers. The challenges in doing so was, how to do so without the teacher noticing and getting into the locked bios. The teacher problem was solved when we got a little bit of time when the teacher would step out of the room sometimes. We picked a desktop that wasn't being used by anyone at the time in the class. The other problem was getting into the bios to boot the drive. Long story short, we were able to switch a jumper on the motherboard to clear the bios settings and let us boot the drive. With Ubuntu installed, it took all of about a day for the school to take that PC to the IT gulag. I think they were very confused and threw it out. We didn't want them to just throw more desktops out so we stopped our shenanigans there.

Used a old password sniffer or something that revealed stored password. Turns out it was the root password for the whole school network LMFAO! Still use the password till this day with added characters 😂😂😂

Notepad could read/write everything so I used it to temporarily disable the dumb software that locked things down to a typing game, a "bible study" game, and Notepad. When they found out I wouldn't admit to anything and they had no idea how I did it. I could literally type faster than the computer could keep up with in the typing game so I could sit back while it caught up to me and still get a perfect score, which really sealed the deal for me that they were wasting my time in "typing class" and it wasn't worthwhile to punish me for whatever it was I did that let me take over any school computer I wanted without apparently changing anything about it that they could figure out.

I realised the school PC’s boot order was A:, then C:, booted into DOS from floppy to get behind their own autoexec.bat, installed my own which just repeatedly echo’d “Teachers suck”.

They had some shitty network config utility, which was relying on a weird script language (from a company called BFC Computers). Anyway, it synced some assets down to customise a series of crappy programs with licenses and “Property of Bangsbostrand Skole” messaging. I changed to it randomly (about once a month, across their fleet or 50-ish PCs) retrieve a different set of strings and pictures which all said “Teachers suck”.

I was banned from the computer lab for a year. They fixed the autoexec issue within a day (after calling “very expensive consultants, young man!!”) but when I left some their PCs would still occasionally display “Teachers suck” instead of “property of” in various programs.

Situation: once in middle school, we had to present something for a class (don’t remember which one) with power point slides

In those days, you had to bring the presentation in an usb pendrive.

For some reason, most of the class didn’t finish it.

I disabled usb ports from device manager.

Saved the day.

discovered a workaround that i could get to the C drive, then discovered a program that could change the wallpaper and info text on the computer (the change was local to that specific computer). had a little bit of fun with that a couple of times. i also brought in a USB stick with Linux Mint installed on it and booted to that whenever i had free time (i mostly browsed the safe side of the darkweb [back when it was still interesting] and made keygen music in OpenMPT). fun times those were. also booting to mint led me to fully switch to linux so ye :)

My school had a shared drive where anyone could create files and folders. There was one folder where people would put random things (bash scripts downloaded from the internet, pirated minecraft, etc.). I wrote a python program that would display a picture of a pineapple on your screen (no ability to minimise, or move other windows in front of it). I had python installed to one of those folders that only appears if you select "show protected operating system files". I later wrote a remote-control script that communicated by creating files on the network. I was able to control the mouse and keyboards, open applications, take screenshots, and monitor keypresses (I never got anyone to click on it without me telling them to though). Never got discovered for any of it...

10 FOR X = 1 TO 20000
20 FOR Y = 1 TO 20000
30 NEXT Y
40 NEXT X
50 BEEP
60 GOTO 50

If WinNuke rings a bell. You remember the fun :-)

Open a small program. Type in the IP address. Click Nuke. Target PC immediately shuts down. While it's rebooting you grab it's IP address as your own so it can't rejoin the network. Worked great in a building where every machine had a predictable fixed ip. Some good teenage mayhem.

Replaced one teacher's desktop background with a screenshot of the desktop, then hid all the icons and minimized the taskbar.

Got admin access on one of the lab computers to install something needed for a class, and swapped out a bunch of the default Windows sound effects (login etc) with random other sound clips.

Torrented Flatout 2 onto one of the library computers and found out years later a bunch of kids were still playing it during lunch/recess

Uni astronomy lab redhat machines accepted single user mode arguments in grub. Created a backdoor user with uid 0 and wrote some code to play some bleeps and bloops every night at 2am. Only did this to one machine to add to the mystery

Booted Macs into single-user mode and set a root password, then logging in with ssh from across the room and killing stuff that other people were running.

Had a class that was just taking old computer parts and building working systems. Installed SubSeven on some classmates’ systems and did shenanigans. Came in handy while we played Starsiege Tribes.

I graduated in 2000. During my 11th year, I had an economics class in the same room as a computer lab. Over the course of a few weeks, I downloaded a voice synthesizer program, Shit Talker, to all the computers and set up scripts to have them all begin "talking shit" about our educationally worthless instructor (he taught because he wanted to coach sports), all sequentially during a class a few weeks in the future.

What I didn't think about is how I was one of maybe four or five computer literate students in my grade, so I was quickly targeted after it went off. I should have just denied having done it but I was a dumb teen; they were bluffing about knowing it was me and I fell for it. I had computer access revoked for the rest of my public school career.

Soooo...a bit later that year, my father brings home a very small, defunct computer from his work. It was this custom job consisting of a tiny motherboard, smaller than a micro ATX, with a couple of daughter boards for all its peripheral connections. He just stole it because he thought it was cool but, being pretty computer illiterate, didn't know what to do with it. I gutted it, installed the innards in a plastic file folder box, and installed Windows 98. I now had a portable computer! I'd carry it to my classes, hook it up to a monitor, and use that instead. I initially caught flak for it but I was restricted from using school computers, not their monitors.

I found a blue screen of death screensaver online and I installed it on all the school library computers back my my freshman year.

Back in college, the old AppleTalk protocol did auto-discovery, so you could open up the Chooser and see virtually all of the Macs on campus. A lot of people didn't understand network security, or were lazy, so they'd share their drives with guest access.

This was way too easy, so for maximum deviousness and WTF'ery, I'd just make edits to a file here and there.

I didn't, but a classmate shoved a piece of pizza in the CD drive.

We could unscrew the chassis of the computer and take whatever hardware we wanted to lol. We never actually got anything but we'd remove the RAM or unplug a hard drive and put it back.

We also found games hidden in certain directories. I even saw someone playing Undertale.

I also found a torrent client running on start up on one of the desktops seeding some movies.

If it counts, we used a program to throttle other devices' WiFi speeds. I forgot what it was called.

Used netsend to send dank memes to every connected PC in the school.

Using WOL to turn them on; fakeupdate.net; using open-airplay to mess with AppleTVs; rotating the screen 180° with Ctrl+Alt+Arrows or sth; sending deauth requests to access points with teacher's MAC addresses

I used them as a sort of thin client into a system that I had root on, so I could do whatever Science demanded of me without asking for access. Permitted, but certainly unexpected!

I would carry a USB stick that just had a VNC client on it. My home server was built from high-end scrap, and was leagues faster than anything the department had at the time, at least for student use.

I also had a Sharp Zaurus I had jury-rigged WiFi into, so I could run data analysis whenever I thought of something. It ran VNC or SSH. This was in the early days before it was called "machine learning" or even "big data". So we take this sort of thing for granted now (hello Google Cloud), but at the time it was magic superpowers to have immediate access to a machine with 4 physical CPUs from a handheld device.

Make a forkbomb on classmates computers and run it.

A teaching seminar was held in one of the classrooms that I took a class in. Students came in the next morning to see a username and password on the whiteboard. It didn't take long for us to test it on school computers.

The account had admin level access and could go into any student's directory. This led to rampant cheating on homework and labs.

I used it on my physics labs in senior year. I, and a few others, were caught and had to make up a few of the labs in the early morning in order to be able to take our finals. Also had detention for weeks.

A year later, after I had graduated and was in college for CS, I applied for a job at the school as a system administrator. The guidance counselor was in the room when I was talking to the IT admin. When I left, she brought up how I had broken policy and accessed files via that breach. The IT admin found me in the hall and asked me about it. I explained that I had taken my punishment, made up the labs, and didn't feel that it would affect my work at the school, but would withdraw my application anyway.

Someone in my programming class told us how unplugging (and replugging) the Ethernet cable at a specific time when logging in gave us full network access. I didn't so much "mess with the computers" as "cheat my ass off, because I had access to all teachers' files."

Nice try, FBI guy. We are not divulging any of our past felonies.

Edit: oh boy, was I wrong...

ITT: people admitting to violations of 18 USC 1030, which is a terrible law that is way too vague.

I graduated high school in 1996 so internet access at school wasn't really a thing at that point. It was planned to be introduced in the next year.