This article investigates how different forms of knowledge are actualised during read-aloud activities in preschool. More specifically, informed by the distinction between two fundamental modes of knowledge or sensemaking, narrative and paradigmatic, we analyse how the latter (typified by scientific discourse) comes to the fore and is responded to during read-aloud activities when a book about a technological problem is read, discussed, and further followed up in a Swedish preschool setting. The empirical data consists of video observations. Theoretically, the study builds on a sociocultural perspective that conceptualises learning in terms of the appropriation of cultural tools and practices. What tools (e.g., forms of knowledge) and practices (e.g. read-aloud ones) children encounter and are supported in appropriating during their early education therefore emerge as critical to their development. This interest informs the overarching research project into read-aloud practices in preschool of which the present study forms a part. The results show that paradigmatic knowledge (here in the form of technology) is generally rendered and responded to in a narrative way. However, the ensuing talk can be characterised as a form of hybrid discourse between these modes. The pros and cons of such discourse mixing is discussed in terms of their implications for children's learning.