This paper investigates affect as part of children's sensemaking in the context of a play-based mixed-reality science learning environment. We build on theories of affect as disciplinary work by investigating the multiple layers of affect that are essential to children's scientific inquiry and to identify pedagogical moves that recognize, value, and build on this affect as integral to learning. Findings encourage educators to affirm children's dignities as scientific inquirers by validating children's diverse and affective resources in the learning process.