A Rasberry Pi. The number of things you can do with these cheap computers is astronomical. You can have a Debian Linux computer and then learn networking, programming, run your own small website. Then start on hardware. Connect up various hardware devices, maybe starting with just a fan. Turn on. Turn off. A second monitor, larger disks. Webrtc. On an on.
You never know what kinds of things kids will like. They may like building a website. Or getting the fan to turn. Or setting the prompt to "hey dude?".
My own experience is that kids like to do things - to see some result. They don't get much of that these days, so anything to encourage that vs being a clickbait consumer is good.
As for games, there were old Freddy Fish, Monkey Island games. Putt-putt does whatever was a favorite. I have not run retro-pi or whatever but I think many of those things are still available.
A pi + a full kit like breadboard/cables, LCD/LED display panels, camera, microphone/speaker, air sensors, IR sensors, gyros, etc. Now that's got a chance.
It's certainly not going to be for all kids but for those with an inquisitive mind once you set them up and show how to display output in various ways they will start to see the potential. From there you can move onto basic rc hobbyist stuff which is more accessible than ever. Buy some cheap brushless motors, wheels and a frame online, make the pi follow you around by sound only.
Yeah, that's what I didn't mention it. I myself wanted one, but there is no way to buy it unless you are fine paying exorbitant prices when it comes for auction on ebay... Which goes against the goal of a low cost computer for learning.
Arduino has the very approachable scratch as a language + beginner friendly ide and a good community but I feel like a pi or similar board that you can drop ubuntu on and run some python scripts opens up more possibilities.
Then point them at chatgpt and see what happens haha.
That's like saying the only novelty of trolley bags are the wheels.
That's. The. Point.
Instead of a closed down consumer hardware like a phone, tab, laptop, there's something that you can physically expand, read data from nature using it, and make changes directly in the physical world using code.
A Raspberry Pi or similar may be a choice only because it is cheap, but otherwise it does not provide any better learning experience than any Intel/AMD personal computer with Linux or FreeBSD.
In order to have a computer that can be completely understood, like one from 40 years ago, the best would be a development board for some Cortex-M microcontroller, e.g. one of the STM32 Discovery kits.
These are very cheap and have complete documentation, unlike a personal computer or a Raspberry Pi.
On such a development kit it is easy to learn anything that could be learned on an 80's computer.
There are 2 disadvantages when compared to the old computers, these development boards do not have manuals intended for newbies, so someone technically competent has to guide, at least in the beginning, whomever wants to experiment and learn with the kit, and secondly, the development kits are not stand-alone, you need a personal computer on which to compile the programs and load them on the kit.
Despite the 2 disadvantages, such a development kit with an ARM Cortex-M microcontroller is the best way to recreate the experience of an old computer.
Using the development kit for direct access to hardware can be combined with learning programming on the host computer, e.g. for GUI programs or games.
I've migrated a number of projects that didn't strictly require a Pi to ESP32/8266 and PandaBoard over the past few years. Depending on what you want to teach and how, there are lots of great SBCs to choose from.
I do like Pi. I might say that arduino or even a knockoff pi might be better fir the simple fact of availability. It's taking a long time (6mo) to get some models of Pi, and they are getting more expensive now.
You never know what kinds of things kids will like. They may like building a website. Or getting the fan to turn. Or setting the prompt to "hey dude?".
My own experience is that kids like to do things - to see some result. They don't get much of that these days, so anything to encourage that vs being a clickbait consumer is good.
As for games, there were old Freddy Fish, Monkey Island games. Putt-putt does whatever was a favorite. I have not run retro-pi or whatever but I think many of those things are still available.