This paper analyses meaning-making processes in a blended setting--face-to-face interaction and web forum--purposely created for collaborative learning activity. The analysis focuses on one pair out of 14 dyads. The dyad comprises two female students aged 17 and 18 who attended a Brazilian third-year state secondary school. We envisioned intertextuality in a seamless thematic flux using a single theme--about everyday problems in the culture--by two different problem-solving tasks. Task#1 required discussing two polemic reports published in an online newspaper: one in favour of using digital technologies in class, the other against it. Task#2 involved perspective-taking, where students should imagine the school in 20 years. Afterwards, the pair participated in an episodic interview focusing on their participation in both tasks. The interactions were video recorded. To map the meaning-making processes, we applied the dialogic thematic analysis looking for centripetal and centrifugal forces. A semantic map was drawn and discussed. Altogether, the paired and grouped collaborative activities in blended learning promoted authorial production. Our dyad achieved reflective meta-analysis when they compared their viewpoints with the perspective of their colleagues by using justifications and explanations grounded in their production, generating reflexivity and agency in dialogue.