Reading comprehensively is a basic skill that requires learning, practice and support of teachers. This skill is also cross-curricular, so it must be taught beyond language subjects, as it is important to guarantee the possibility of lifelong learning across all issues. This paper addresses the importance of teaching pupils about comprehensive reading in science classes, through cooperative learning and peer and self-assessment models to help students to improve reading comprehension. Results of the work in cooperative reading achieved by three highschool group classes are analyzed and the use of peer-assessment and self-assessment in the educational assessment, as a tool to evaluate the usefulness of cooperative reading in the teaching-learning process. Finally the results of an opinion questionnaire about the students’ experiences in the cooperative reading work are described.