No. The first book is targeted at that age maybe, but I wouldn't read book three to a twelve year old, and five or six get really nasty.
Stephen King put it this way in his review: Harry Potter books are meant to grow up with the child, while many other childrens' books series target a specific age range.
Today you can buy and read all Harry Potter books at once, but it's actually best to follow the release times and keep a year or so between books, if the child is younger.
