The hereby research study is intended to assess the effectiveness of an intervention program built on the integrated teaching strategies of the unit contents in readiness grade by using integrated lesson projects and cooperative group methods that should lead to the development of cooperative skills, positive interpersonal relationship, but also the development of learning abilities and skills, for the subject children in the experimental lot (n=21) as compared to those in the control one (n=22). The research tools were The Classroom Life Survey, designed by Johnson&Johnson (1983, 1996) and adapted for the Romanian population by C. Popa (2010) and Assessment Report for the Development of Children in Readiness Grade.The intervention program was conducted on a six-week period, with a 2-day frequency per week, thus including 14 lesson projects of integrated activities, implemented for school subjects from the readiness grade curriculum, following the timetable of the school days chosen for this program. The research findings show that the integrated approach in the activities with the readiness grade leads to an improvement of cooperation between children, of the interpersonal relationship and of the learning abilities and skills.