Fischer was keen to distance himself from things that bore his name but which he did not completely control the content of. Of course it's well known he was upset over the movie title "Searching for Bobby Fischer", as well as unauthorised changes to "My 60 Memorable Games". I never heard a thing out of him over "Bobby Fischer Teaches Chess" however. Though he wasn't sole author this leads me to believe that at least he approved of the book's contents. I seem to remember he even had the book available for free download on his website, though it appears his website has now disappeared.
That said, I never read the book. It seems to be aimed at beginners but in discussions of recommended books for beginners I rarely hear it mentioned. For this the "For Dummies" or "Complete Idiot's Guide" books are a good bet. They're more than $7.99 mind you, but you can borrow one or both from almost any library.
Is this a good book? Worth the hefty $7.99 (lol)? Did he really have much to do with the creation of it?