This study, undertaken in Singapore, investigates aspects of students’ motivation in undertaking Project Work (PW), and explores the link between motivation and the quality of students’ discourse during group discussions. It uses a Self-Determination framework to answer questions on students’ perceived satisfaction of basic psychological needs, motivation and performance outcomes. Analysis of students’ discourse during PW helped to substantiate survey findings, which showed that the participating students perceived satisfaction in the need or competence and relatedness, but less in autonomy support. Furthermore, many students were extrinsically motivated in PW, appreciating its value but not necessarily finding enjoyment in the process. Students’ talk during PW group discussions tended to be of the practical (problem-solving) mode and cumulative (collaborative, non-critical) type. The findings suggest that, in order to enhance motivation and task engagement, students should be encouraged to share knowledge explicitly and to make their thinking visible through discourse.