This paper deals with the phenomenon of student overload in Croatian primary schools, focusing particularly on the curriculum as one of the most important factors of quantitative overload in this context. Quantitative overload occurs when students spend so much time doing school-related tasks that they become overburdened. The aim of the present study was to investigate whether the cur- riculum needs to change in order to reduce student overload and whether the school infrastructure could support the necessary changes. The analysis confirmed the existence of student overload and indicated that the curriculum should be reconfigured in order to decrease this overload. An analysis of curricula in use between 1958 and 2016 showed that student overload is increasing, despite constant efforts to alleviate the problem. Some of the impediments to reduction of student overload can be attributed to the curriculum, as well as to the organisation of the school day. The collected data revealed that there is insufficient school capacity for the necessary reorganisation ; specifically, schools lack the resources to make the switch to a single-shift school day and to provide teaching assistance during extended-day programmes to allow students to complete all their school-related tasks at school.