<p>The purpose of this study is to scrutinize Lithner’s (2008) Creative Mathematical Reasoning (CMR) framework in the context of 7–8-year-olds’ reasoning. The research field lacks attention to novelty aspects of reasoning in early primary school, which is at the core of the CMR framework. Constituting a unique target group with respect to mathematical reasoning, two groups of 7–8-year-olds were video-recorded as they engaged in The Coin Task, which is a non-routine CMR task facilitating novel reasoning. The students’ mathematical reasoning was analysed using the CMR framework. The students exemplified both creative mathematical reasoning and algorithmic reasoning. However, the analyses uncovered challenges related to the operationalization of ‘novelty’ and ‘plausibility’ in the context of 7–8-year-olds, which are two key characteristics of CMR. Novelty, operationalized as a context-dependent ‘personal novelty’, may be difficult to establish among these students. Furthermore, 7–8-year-old students may comprehend the plausibility of their reasoning without having the vocabulary to express it or seeing the need to do so, thus not being attributed with CMR. This study demonstrates that, with respect to applications of the CMR framework in early primary school, the notion of ‘novelty’ warrants further exploration, and the plausibility criterion may require reconsideration.</p>