Previous research on the role of prior skills like proportional reasoning skills for the development of mathematical concepts offers conclusions such as "more (prior skills) is better (for later learning)." Insights, which prior skill "level" goes along with which "level" of learning outcomes, may advance the…

Being able to perform computational estimations efficiently is an important skill. Furthermore, computational estimation experiments are used to study general principles in strategy development. Rounding strategies are common in computational estimation. However, little is known about whether and when children use a mixed-rounding strategy (i.e.,…

Mathematical arguments are central components of mathematics and play a role in certain types of modelling of potential mathematical giftedness. However, particular characteristics of arguments are interpreted differently in the context of mathematical giftedness. Some models of giftedness see no connection, whereas other models consider the…

Although scientific reasoning is not a formal, independent school subject, it is an increasingly important skill, especially for student learning in science, technology, engineering, and mathematics (STEM) subjects. To promote scientific reasoning effectively, it is important to know its influencing factors. While cognitive influences have been…

Teacher judgments impact on students' academic development, yet studies have revealed only modest judgment accuracy. Identifying biases hampering judgment accuracy is crucial. The present study scrutinized one such bias, namely reference group effects on teacher judgments (i.e., systematic relations between class-average ability and teacher…

Theoretical analysis of whole number-based calculation strategies and digit-based algorithms for multi-digit multiplication and division reveals that strategy use includes two kinds of reasoning: reasoning about the relations between numbers and reasoning about the relations between operations. In contrast, algorithms aim to reduce the necessary…

This article presents a reanalysis of the data of 862 second and fourth graders collected in two previous studies, focusing on the influence of method (psychometric vs. chronometric) and stimulus type on the gender difference in mental-rotation accuracy. The children had to solve mental-rotation tasks with animal pictures, letters, or cube…