Books with highlighting and writing in them will be accepted as long as no more than 25% of the pages of the book include any markings. Study guides, work books, lab manuals, working papers, practice/exercise books, activity books and any books with blank answer fields must have NO writing OR highlighting in them in order to receive payment. Any books that have damage such as a loose binding, cover or pages partially or entirely torn off, mold damage, stuck pages, water damage of any kind, loose or missing pages, or pages with tape or other foreign materials bound to them will not be accepted.