There are five compulsory subjects including mathematics in the secondary school level in Bangladesh. Teachers in the mathematics classrooms follow the teacher-centered teaching method in the rural secondary schools context. This Conventional Teaching (CT) method has been affected to Secondary School Certificate (SSC) examination, the first public examination in the country. The pass percentage of SSC examination in the rural schools is below twenty per cent as well as there are no students of a large number of schools passed the SSC examination in the year 2005. To solve this arising problem, it is a crying need to introduce the teaching-learning strategies that are well documented and globally well known. As cooperative learning (CL) is supported by a number of renowned educationists and it has significantly improved learners’ performance in mathematics achievement so it is plausible that CL small group approach can be the alternative way to be implemented in the rural secondary schools to tackle the SSC mathematics disasters. The aim of this research is to find out the effectiveness of CL in comparison to CT on students’ mathematics achievement as well as identify students’ and teachers’ attitudes towards CL in selected rural secondary schools in Natore, Bangladesh. The researcher will employ a quasi-experimental design in order to find out the effectiveness of CL. It is hoped that this study will be able to identify appropriate measures that could be promote CL approach in rural secondary school mathematics classrooms in Bangladesh.