This paper is based on an action research carried out in two Kenyan Primary schools in Nairobi. The purpose was to implement group work and pair work to improve teaching and learning in large classes by creating interaction opportunities for learners. This was a mixed method study of dominant/less dominant design where interviews and structured and unstructured observations were used as methods of data collection.The study established that systematic incorporation of cooperative learning basic elements in group work made it more viable in creating interaction opportunities for learners in large classes. Though pair work was modified to enable learners to be interactively accountable both at individual and level and as pairs, it was not as successful as expected.