I checked out Armadillos(Nature’s Children series) for a unit in Science for my 1st grader and my preschooler and I loved it. It is 48 pages (including the index) so it is substantial enough to have a good reading time. It has many sections that elaborate on specific points that were briefly mentioned in the The Kingfisher First Animal Encyclopedia (Kingfisher First Reference) chapter. My first grader could read many of the words but still needed some guidance but it is not real juvenile so one could use it probably in higher grades also. This is a book I will use again with other children.