I don't know if VMs are as good a solution as a RaspberryPi(-alike). VMs are part of the 'important' machine, rather than being separate; using the same keyboa

I don't know if VMs are as good a solution as a RaspberryPi(-alike). VMs are part of the 'important' machine, rather than being separate; using the same keyboard, mouse, monitor, etc. there's always the risk of e.g. typing into the wrong 'important' terminal by mistake. Plus, a VM is like a "computer simulator" rather than a computer; introducing a guest OS certainly wouldn't prevent me wanting to play with the host OS, and I'd worry that keeping the host off-limits would allow "magical thinking" regarding how the machine operates. It's also probably more empowering to be given a real, physical box too. Whilst the RaspberryPi is inexpensive it's still a real computer, running real software, which a child can own and make their own. VMs, like all virtual entities, can't be "owned" in the same way (e.g. see copyright).