Naturescope has been used by thousands of teachers during the past decade. During that time, it has been in print/out of print several times. It was originally produced as part of National Wildlife's Ranger Rick series, later was published by Harcourt Brace, which has now discontinued printing it. We purchased the last remaining stock of both soft and hardcover NatureScopes which we will offer as long as supplies last. The hardcover versions are library bound for maximum durability, hence their higher price (compared to softcover).