Since the 1920ies researchers have been studying children’s temporal concepts, concluding that the concept of time is complex and difficult to teach children (Fraisse 1984, Kelly, Miller, Fang & Feng, 1999; Piaget 1969; Zakay 1989). A dominant perspective in the available research focuses on when children acquire certain time-related competences such as clock reading (e.g. Piaget 1969; Friedman 1982; Levin and Gilat 1983), and does not focus on underlying cognitive processes. As such, the available theoretical and empirical evidences is not helpful to understand what makes time so difficult for children to grasp. This is especially critical when it comes to the teaching of time concepts. For example, Foreman and colleagues (2007) point out that the reading and writing of clock times is difficult to teach because of the engagement of a complex of interrelated sub-competences. But there is hardly research available illuminating these sub-competences or specifying the learning process involved in the acquisition of these competences. An important question in order to understand the difficulties involved in the acquisition of skills such as reading the clock and measuring time intervals is how these time-related competences relate to other mathematical skills such as arithmetic and knowledge of numbers. Based on Case’s theory of cognitive development (1985, 1992) describing the processing demand of categories of tasks, and asserting that cognitive development takes place recursively in that earlier separate operations are integrated to produce higher order operations, it can be assumed that (1) the development of time-related competences evolves gradually and (2) simple time-related competences, such as reading hour times, are related to basic mathematical skills and more demanding competences such as measuring time intervals. Although time, defined as a component of a measuring system used to sequence events, to compare the duration of events and the intervals between them, is mainly incorporated in primary school mathematics, it can be assumed that next to mathematical skills, time-related competences are also connected to linguistic and visuospatial abilities. The purpose of this empirical study is to identify the role of mathematical, visuospatial and, to a lesser extent, linguistic skills in the learning of time-related competences in order to get into a deeper understanding of the complexity of the concept of time and the learning process involved in the acquisition of time-related competences during primary school.

809 Flemish (Dutch speaking area of Belgium) children from each of grades 3 - 6 participated in the study, resulting in a sample of 276 third graders, 303 fourth graders, 124 fifth grader and 106 sixth graders. Mean ages for the four grades are 8.3, 9.4, 10.5 and 11.4 years. In the study, a test battery was used containing the Shortened Visuospatial Questionnaire (SVS, Cornoldi et al., 2003), the Tempo Test Rekenen (TTR; de Vos, 1992) measuring arithmetic skills, the Kortrijkse Rekentest Revisie 2006 (KRT-R, Baudonck e.t al., 2006) testing for knowledge of numbers and arithmetics, a test on fractions in three levels of difficulty and a test on time-related skills containing the reading and writing of analog and digital clock times, measuring time intervals, transforming analog into digital times and vice versa, solving time problems, using a calendar and using time-related vocabulary.

The acquisition of time concepts is expected to evolve gradually, with different processing demands in different grades. We expect children’s performance on time-related skills to be related to their mathematical performance. In grades 1-4 we expect that children who are accurate in counting and arithmetic will be more accurate in telling time than their peers who have difficulties with basic mathematical skills. In grades 5 and 6 we expect the accuracy in solving time problems to relate to more complex mathematical skills such as fractions and visuospatial and linguistic abilities are expected to play a role in the acquisition of time concepts.