Linux

It's where Linux really shines, to be honest. Those specs will be fine. Great learning opportunity for the students too.

This is my rule of thumb and process to choose DE and distro:

1. Find the CPU model and do a google search with it and the word passmark. The passmark page will tell you how fast the cpu is. If it's between 500 and 1000, use XFce as your desktop environment. If it's between 1000 and 2500, you can use Cinnamon (Linux Mint). If it's more, you can use kde/gnome. If it's less than 500, use LXQT or LXDE.
2. How much RAM there is in there. These days, you need a minimum of 4GB of browse the internet (the DEs/distros themselves might use less than 1 GB of RAM, but the moment you open a web browser in this day and age, all hell breaks loose with memory usage). For best performance, 8+ GB is better.
3. Ensure that it has over 16 GB of a drive. At 16 GB (as in some old Chromebooks), only Debian fits these days (with 6 GB free space after installation). Mint and the others prefer over 24 GB (both fedora and all the ubuntu-based ones are too big to fit in 16gb without issues -- debian fits).

Using these rules, I've converted many laptops and computers for my family here in Greece, installing the most appropriate each time. The least powerful computer was my mom's old laptop, with 16 GB internal, 2 GB of RAM, 600 passmark points. As long as she's only opening 1 tab on Chrome (Debian/XFce), she fits in the 2 GB RAM without swapping (most of the time). I use Chrome and not Firefox for these older laptops because Chrome uses LESS memory than Firefox (there's an additional setting for it in the settings to help the matters more), and its youtube playback speed is much better too. I use firefox on more powerful computers, and it's my default too, just not for underpowered computers.

Friend of mine runs Linux on a 15 years old cheap consumer laptop, and it's working smoothly for browsing.

Just try. There's no risk and no costs trying. Have fun.

If they can run Windows 7, they can run any Linux.

We’re talking pre-7th gen i5’s

My gaming and photo editing PC has a 4th gen i5.

useless

pre 7th gen i5's

We must live life on completely different parameters

useless

pre-7th gen i5’s

I’ve got systems with second and third gen i5s that are handling Windows 10 just fine, seems like what the school really needs is some SSDs.

Linux would definitely run better, so that’s worth it too.

If this school is heavily embedded im the Google ecosystem, ChromeOS Flex is an option. FydeOS is similar but without the Google Account requirement.

The biggest demands will come from the browser and its media players, not the OS. An i5 with 4gb RAM will be ok. Anything less will be marginal or worse. The modern web sucks. Did you know that mobile phones are starting to come with cooling fans? OMG.

Windows 7/8 ... "Old machines"...

....

Am i this old ?

daily drive Arch on a Core i3 550 ,I think you'll be able to figure out something

I highly recommend scavenging the machines, you're going to have your best chance with the machines if they're maxed out on RAM even if you end up with 1/4th of the total machines

As long as you can secure them it should be fine, and as long as you can deal with the user account issues. You’ll either need to join them to your Windows domain or explain to people why they can’t use their normal username and password. You’ll probably find the kids understand it better than the teachers.

Got with Xfce edition of either EndeavourOS (Arch based) or Mint (Ubuntu based). They’re both easy to set up.

XFCE is a lightweight desktop environment with all you’d expect from a Windows 7 machine (and more).

That covers a pretty wide range of hardware, but that era would be around 2009-2015, give or take, so you would be looking at around Intel 1st gen to 6th gen most likely (Let's be honest, there is nearly zero chance institutions would be using anything but Intel in that era). Pentium-branded CPUs from that time range, unfortunately, likely means low-end dual core CPUs with no hyperthreading, so 2C/2T, but I have run Linux on Core2-era machines without issue, so hopefully the CPU specs will be okay.

2-8GB of DDR3 RAM is most likely for that era, and as others point out, will be your biggest issue for running browsers. If the RAM is anything like the CPUs, I am assuming you will be looking at the lower end with 2-4GB depending on how old the oldest machines you have are, so I second the recommendation of maybe consolidating the RAM into fewer machines, or if you can get any kind of budget at all, DDR3 sticks on ebay are going to be dirt cheap. A quick look and I see bulk listings of 20x4GB sticks for $26.

In terms of distro/DE, I second anything with XFCE, but if you could bump them up to around 8GB RAM, then I think any DE would be feasible.

Hard drives shouldn't be an issue I think, since desktop hard drives in the 320GB-1TB range would have been standard by then. Also, you are most likely outside of the "capacitor plague" era, so I would not expect motherboard issues, but you might open them up and dust them out so the fans aren't struggling. Re-pasting the CPUs would also probably be a good idea, so maybe consider adding a couple $5 tubes of thermal paste to a possible budget. Polysynthetic thermal compounds which do not dry out easily would be preferable, and something like Arctic Silver 5 would also be an era-appropriate choice, lol.

Instead of you installing linux on them, why not make it a project for the kids? Give them a bunch of distros to try and see what they learn.

My son is using my 12 year old Asus 1215 netbook, that cost 300€ back then with Xubuntu to learn programming. Works fine. He can even run Minecraft on it. It glitches a lot though. It has an Intel Atom cpu...

We first tried Linux MX, but Xubuntu runs better.

It's exactly what I did when I was a student. There was an old pc that had a broken winXP install. I put Xubuntu on it and made it publicly accessible to the students. They loved it.

Just throw a USB stick on them and boot something like Linux Mint (defaults are pretty similar to Windows, should be obvious to anyone how to use it) to see how it runs with no installation and maybe showcase that to someone who could decide explaining briefly what it is and how it’s more lightweight.

I assume these have still some mechanical drives and that will probably be their biggest slow down. Upgrading to SSDs (which is still a lot cheaper than full computers) would bring them second life.

The i5’s have plenty of power for web browsing machines and can still be pretty snappy. Pentiums (4’s?) not so much, but it’s also worth trying

I still use my i5-4670k machine. It has a SATA SSD, only 8GB RAM, but it is a completely zippy machine. Ancient (by today's standards) 750Ti, but I only rarely use it for old games (Xonotic and Portal2) and it doesn't break a sweat.

Debian, i3wm, so it ends up being lightweight but that's my preferred setup regardless of specs.

I think you'll find these machines are exceedingly usable when you put a non-bloated OS on them

FreeGeek Portland has (had?) a sign: we clean windows.

All donated computers are scrubbed of previous data, tested & reassembled (if needed) & have Linux installed.

Oldest to newest hardware work fine.

Work 24 hours to take a system home. Training is free.

Edit. Adding:

They have a website & videos on how to use Mint OS (for browsing, gaming, homework & basics) for kids of all ages: FreeGeek Online

Yes of course it’ll work fine.

I use a third gen i5 laptop as a daily driver and run mid-poly count cad and cam, host windows vms and do everything else but play games that people expect out of a computer (no time for games nowadays).

Look into installing more ram and ssds in the old desktops and they’ll skip along happily for another decade or until mainline kernels drop support for their instruction set. I’m running Debian and rhel (seriously look into this, they have programs to get cheap licenses into the hands of educational institutions and provide good support) but probably anything is fine, just figure out account security so kids don’t go around copy and pasting whatever stack exchanges llm suggests into bash.

E: I read the rest of the thread and there’s a lot of “this worked for my computers/this worked for me” advice. Not hating, I literally gave that exact advice myself.

Call red hat sales if you’re in the us, I guess suse sales if you’re in europe or india. They’ll most likely set you up with a pilot program license and if not they’ll walk you through the process of creating one or two accounts to work around the “ten free machines but then you gotta pay” limitation.

You’ll be able to sell it to administration as “this program gets students in the drivers seat of the systems used for stem research, ai and android development for minimal upgrade cost and no new units. Developing familiarity with these systems will give students who pursue those studies a tangible advantage over their peers.”

If you have coworkers in computer education or it, sell it to them as a path to get more certs at a reduced or nonexistent cost (red hat and suse have their own cert programs that they use for training like ms and cisco do).

Good luck!

totally doable. But if you yeet the bloat, windows 10 will be more than fine. My dad runs windows 10 on a i5 2430m all in one. My old school computers had i5 2400s and 4 gb of ram and they ran windows 10 without too much issue.

They're unlikely to do worse than my laptop from 2008, and it's perfectly usable under Linux (bit of a lag when starting up large programs, that's all). As has already been said, go for a lighter desktop environment (XFCE, LXQT, Mate, TDE) unless these machines were high-spec'd for their era. For the oldest machines, you might want to consider installing Puppy Linux rather than one of the more mainstream distributions, since Puppy specializes in old x86-family hardware.

The hardware is totally fine, Linux requirements didnt really change at all in the last years.

KDE Plasma is a really well maintained desktop, poorly also with a ton of customization. It has a very familiar user experience. GNOME is also nice but not familiar at all.

On these machines, recommendations:

• some stable distro like Debian 12, with automatic background updates
• OR an atomic distro like Fedora Atomic. (Still waiting for CentOS bootc, which would be the best of both worlds. Or Rocky/Almalinux Atomic)
• GNOME or KDE

best would be to always delete the user account, so they need to store stuff on a network drive. That way they cannot permanently break a desktop, but you still dont need active directory stuff.

Be aware that managing many PCs is work. Keep it as simple as possible, install apps as systemwide flatpaks, keep the OS minimal, automate updates.

Maybe have a look at ansible, I think it is complex but the learning curve is worth the effort if you need to manage more than 4 machines.

Zorin OS has a lite version, you could test that and see if it works. Besides, it's one of the best distros for people used to Windows so it wouldn't require much work to help people to figure out how to use it.

Go mx linux fluxbox

As others have stated, reviving them through Linux should be a piece of cake.

However, how many is "a tonne"? This is important information for the community to provide recommendations on administrating those systems.