To be fair, I'm a little conflicted on what to say about this book... Is it my least favorite? Far from it; reading the book was easy enough and I found the main character quite pleasant. But this is American history through decidedly rose colored lenses. While history has shown us that there were indeed men such as At-mun, whose name was changed to Amos Fortune I think that they were few and far between. And even those slaves which led decent lives were still slaves. This is a horror which is glancingly addressed in the text; this would not be an appropriate introduction to slavery for young pupils, lest they believe that being enslaved is more of a sad inconvenience than anything.
The years when Amos has paid for his freedom and that of four others are the most interesting parts of the book to read (and thankfully the bulk of the book) but even then the segregation he experienced is only passingly mentioned.
I don't think this is the worst Newbery. I don't even think it is a bad book. What it is a certainly a product of when it was written, a book that never ventures too far into the historical realities of slavery. Should children read this book? Perhaps, but only after they have seen the ugly, ugly side of slavery in America and have come to understand that just because someone (such as Amos) had a good life here, doesn't make that right.
