We focus on teachers' ways of leading whole class discussions (WCDs) in mathematics, with the goal of uncovering their traces (if any) in their students' responses (a) while participating in the WCDs and (b) in the written responses in a final test. For this purpose, two 8th-grade probability classes learning a 10-lesson unit with different teachers were observed. Our data sources include (1) video-recordings of the WCDs and (2) the responses of students to final test items. We analyzed the teachers' talk-moves, students' accountable participation, and students' reasoning in the final test items. Interweaving the findings from all analyses we found differences between the classes in students' ways of participation in WCDs and in their corresponding final test responses. The teachers' ways of leading the WCDs contribute to the explanation of these differences.