This definitely benefits from sentimental nostalgia since I really relied on (and often reread) it in elementary/middle school, at which point in my life it was a valued resource.

So it doesn't seem very fair to rate it based on what I've since learned about mental health and myself, especially now that I've aged out of the target audience. My only note is that I wish it talked more about mental illness since they have a huge impact on emotions (there's a sidebar checklist of depression symptoms, but that's about it) — but I have no idea what the mental health field looked like in 2002, so I'm not condemning the absence or anything.