The aim of this research is to determine the effects of problem based learning on students success, attitudes towards course, metacognitive awareness and motivation level in the Primary Education Science and Technology course. The research was carried out on two different groups of the sixth grade students of IDV Bilkent Private Primary School in Ankara. In the research, to which pre and post-test with control group design were applied, achievement test, attitude scale, metacognitive awareness scale and motivation scale were used as data collection tools. Both the experimental and the control group were found to be equivalent in terms of first semester school reports, achievement, attitudes, metacognitive awareness and motivation levels prior to the treatment. The problem based learning approach was used in the experimental group yet no intervention was made to the control group. The results obtained at the end of the research indicated that there was a significant difference between the experimental group which was exposed to problem based learning and control group which wasn't in terms of success, attitudes, metacognitive awareness and motivation means in favour of the experimental group.