How Close does the Movie follow the book?

I love this movie-after all it has Lloyd Bridges and John Caradine-two Hollywood veterans lend able support to the less experienced child actor Michael Link who plays the lead.

What I love about this film is the way the characters are played. The adults are not wimps and the kids are not sappy. They made EJ a likable kid-a precocious young man who doesn't pretend to know more than he does.

What I wonder is: How close is the movie to the book? I recently ordered the book and plan to read it when it arrives. I guessing that it takes liberties with book-since it's so easy to predict. Of course the book is always better than the movie 99% of the time.

I don't feed trolls--I eat them(for breakfast!!)

Jay