Donate

As we, your fellow users, do not know where you are—and these are world-wide English-language forums—that is hard to answer. That said:

1. Public schools are likely running managed, linked computers, so a different model coming in as a donation may not work with their system. However, a school may know of a needy student that can benefit from even an older Mac.
2. Private schools may be glad to have it.
3. Were it mine I would see if veterans' homes or long-term care facliteis have any residents who cannot afford a computer.

Whatever path you choose, make sure you carefully read and follow this Apple article before donating, or the next owner may not be able to use it:

What to do before you sell, give away, or trade in your Mac - Apple Support

I had an interesting thing happen the other day. I took a working old monitor to Good Will to donate. They refused it saying they had plenty of them and there was no demand for monitors that old. I found that very interesting, even those in need of a free monitor wouldn't take just any old tech.

I ended up donating it to "Junk in a Box"; paid to have it hauled off ... that and a pile of other junk.