I just don't know if it would work well as a library book, since the pages are meant to be cut out and folded up into planes. Of course, a responsible child would refrain from doing so and just copy the designs onto their own sheets of paper.

Library will just sell it in their book sale.

yes. most libraries do not actually accept donations for circulation, so ask before you donate

That likely will make sure it goes to someone who cares about it, for what it's worth.