4.5 stars (as an adult). 5 stars as a middle grader.

This was one of my favorite books as an early chapter book reader and was likely my introduction to the areas of sci-fi and fantasy in fiction. I don't recall reading anything in that genre prior to it. I had a love of this book that was so intense that it stuck with me for several years, despite not having read it for several decades and having forgotten the near totality of its plot. This reread was very fun for me -- especially listening to the audio version. It did not hold quite the same level of magic as it did when I was younger, but I still really enjoyed it and can see so many valuable moral lessons within the plot. There is definitely a nostalgic love for this book in my heart, but I also enjoyed it very much as an adult and look forward to now completely reading the series.