Two separate studies, Jonsson et al. (J. Math Behav. 2014;36: 20–32)and KarlssonWirebring et al. (Trends Neurosci Educ. 2015;4(1–2):6–14),showed that learning mathematics using creative mathematical reasoningand constructing their own solution methods can be moreefficient than if students use algorithmic reasoning and are giventhe solution procedures. It was argued that effortful struggle was thekey that explained this difference. It was also argued that the resultscould not be explained by the effects of transfer-appropriate processing,although this was not empirically investigated. This studyevaluated the hypotheses of transfer-appropriate processing andeffortful struggle in relation to the specific characteristics associatedwith algorithmic reasoning task and creativemathematical reasoningtask. In a between-subjects design, upper-secondary students werematched according to their working memory capacity.The main finding was that the superior performance associated withpracticing creative mathematical reasoning was mainly supportedby effortful struggle, however, there was also an effect of transferappropriateprocessing. It is argued that students need to strugglewith important mathematics that in turn facilitates the constructionof knowledge. It is further argued that the way we construct mathematicaltasks have consequences for how much effort students allocateto their task-solving attempt.