In the recent past Bangladesh has achieved considerable improvement in enrolment, attendance and school completion rate but little success has been wrought in improving the quality of education. There are many primary school systems in Bangladesh that provide primary education to the children of 5 to 10 years of age using different curriculum and administrative structures. The variety of offered primary education, aimed at eradicating illiteracy, is appreciable if the quality of education remains above an acceptable level. But some recent studies indicate that the quality of primary education is not up to the mark for some school systems and ariations among the systems are glaringly obvious. This low level of performance may be due to a number of internal and external factors including classroom culture and the administration process of the relevant school system. As learning takes place in a classroom and as the teachers re the hubs of all the classroom activities, these case studies intended to delve into the matter to improve understanding of the factors responsible for differences in performance in different school systems. It is obviously easier to conjure up and blame the different curriculums of the various school systems as the main culprit for the differences in performance. However, the real causes of substandard performance and possible explanations of the differences can only be identified through classroom observation. This is what the method that this research uses.