Maybe this is a hot take. However, a lot of the Chromebooks that were deployed by schools during covid are build like tanks while being super lightweight and having great battery life. Meanwhile the old thinkpads are 10 years old and are probably starting to wear down. Many Chromebooks support coreboot these days so theoretically they have the potential to be more private and secure. Some of them are also arm which means that they are more efficient from an architecture perspective.
Edit:
I like how incredibly controversial this is. I have successfully split the votes
At least here I’m pretty sure schools just buy them because they come laughably cheap. Actually, my middle school’s laptops weren’t very durable either but just cheap.
Actually, now that I think of it, Chromebooks can be manufactured by anyone just like Windows laptopa, a Chromebook is just any laptop with ChromeOS pre-installed. There are probably well-built ones (maybe by Lenovo, even?) and there are probably flimsy-made ones, depending on your manufacturer?
Google ran a huge push to get these into schools too… There was a LOT of pressure on Schools to adopt from various partners (or at least that happened in the UK)…
Google is aware of the Microsoft gains from getting people used to their products at a young age…