Considering the vast amount of information on fourth graders’ poor skills in reading comprehension, especially when reading literary and informational texts, and the general agreement on the teaching methods being the main culprit, it was decided to examine the use of the cooperative method of teaching reading as a possible solution for the said problem. A random sample of 100 fourth graders from among 2887 such students in School District 18, was divided into four groups, two experimental groups, and two controls. All groups, before and after the treatment, were given the Reading Literacy Test, taken from PIRLS 2011, and based on two texts, one literary, and the other informational. Data analyses revealed that the use of cooperative method in teaching reading significantly improves reading comprehension skills right across the board.