Dissertation (MA Education)This study investigated the Nursery Level Children Performance on Piagets‘s Conservation Task in primary schools in Dodoma Municipality. The main objective was to determine the nursery class performance on mass, weight and volume conservation task. The study employed Within Participant Reapeted Measure Design with quantitative approach. In this study, a total of 72 respondents from 2 primary schools, one public primary school and one private primary school were selected as sample 72 respondents were nursery class children from selected primary schools. The sample of nursery class were obtained through simple random sampling technique. The data were collected through experiment test, data analysis was done by involved content analysis, calculating mean and independent ’t’ test using SPSS version 20.0. The findings revealed that nursery class children in Dodoma Municipal primary schools, they have conservation problem. There were serious problems on conservation tasks to the nursery children to public primary school and private primary school. The study recommends intensive and adequate materials for teaching conservation tasks teachers and the MoEVT in collaboration with private sector and other partners in education to ensure adequate provision of materials for teaching conservation in all primary schools. Generally the results supported Piaget's theory of cognitive development whereby older children performed better than younger children on conservation tasks. In conclusion, the results of this study agree with Piaget‘s theory of cognitive development.