Finally, a great introduction includes a great connection. "Before we get our new books today, let's think about going to the park. What do you think you would write about if you were the author of a book about the park.?" As the students tell you things about the park, make a list. When the students are reading the book, they can put a check mark by the things in the book. This is also a great segue into a writing lesson (write what the author left out of his book about the park.)
Don't forget, introductions can do lots of the work for you, if you let them.