In XVII century, presumably between 1637 and 1638, with a note in the margin of Diophantus' "Arithmetica", Pierre de Fermat stated that Diophantine equations of the Pythagorean form, x[superscript n] + y[superscript n] = z[superscript n], have no integer solutions for n > 2, and (x, y, z) > 0. Of this statement, however, Fermat…

A teacher of mathematics knows mathematics as a teacher and as a mathematician. Whilst the existing research on teacher knowledge contributes to our understanding of the ways of knowing mathematics as a teacher, little is known about ways of knowing mathematics as a mathematician. Guided by the conceptual framework of mathematical practices (MPs)…

Two problems, both from Gaspar Nicolas' "Tratado da Prática d'Arismética", published in 1519 are considered in this study. The tasks were carried out using pencil, paper and students from Portuguese schools. The aim was to explore the following students' performances: 1. The students were able to recognize the "error",…

For over a decade, Which One Doesn't Belong? (WODB; Danielson, 2016) has been a beloved classroom routine that invites students to engage in mathematical decision-making and justification. In the WODB routine, four related figures are shown to students, and they are asked to decide which of them doesn't belong with the other three. The beauty of…

Author Pam Harris argues that teaching real math--math that is free of distortions--will reach more students more effectively and result in deeper understanding and longer retention. This book is about teaching undistorted math using the kinds of mental reasoning that mathematicians do. Memorization tricks and algorithms meant to make math…

Solving math word problems (MWPs) involves uncovering logical relationships among quantities in natural language descriptions of math problems. Recent studies have demonstrated that the contrastive learning framework can assist models in identifying semantically similar examples while distinguishing between different mathematical logics. This…

The aim of this study is to develop a descriptive framework for teacher educators to assist teachers to plan and realize modelling implementations in their classrooms and for researchers to describe and analyse how modelling is implemented. The planning process and implementations of 12 middle and high school mathematics teachers who conducted…

In this paper, we explore the role that examples play as mathematicians formulate conjectures, and we describe and exemplify one particular example-related activity that we observed in interviews with thirteen mathematicians. During our interviews, mathematicians productively used examples as they formulated conjectures, particularly by creating…

This study examined how word-problem characteristics influenced students' learning and retention of word-problem knowledge during and after an intervention. The participants were 221 fourth-grade students (average age at pretest = 8.8 years) who experienced word-problem difficulties (WPD) and had received a word-problem intervention in third…

The multiplication principle (MP) is foundational for combinatorial problem-solving. From a units-coordination perspective, applying the MP with justification entails establishing unit relationships between the number of options at each independent stage of a counting process and the total number of combinatorial outcomes. Existing research…

This study examines the impact of working memory capacity and mathematics anxiety on the creative reasoning of prospective mathematics teachers, highlighting how these cognitive factors shape problem-solving processes. This research used a mixed-method sequence explanatory method with a sample size of 60 people for quantitative research, and four…

This study aims to reveal the mathematical reasoning process of 8th-grade students and the reasoning indicators they use in this process. The study was carried out in line with the data obtained from the Mathematical Reasoning Test (MRT) administered to 292 8th-grade students. The mathematical reasoning performances of the participants were…

Mathematical thinking is closely related to students' success in solving mathematical problems. Local culture can be a resource to teach mathematical thinking skills. Nonetheless, a lot of teachers still struggle to help students develop their mathematical thinking abilities. This study aims to investigate the ethnomathematics approach applied by…

This study aimed to examine the effect of using the flipped classroom model on students' proportional reasoning. In this context, the study focused on students' achievement and solution strategies for proportional reasoning problems. The participants of the study were 56 seventh-grade students, who were determined by convenience sampling method.…

Many studies highlighted the importance of mathematical justification in problem-solving. This paper describes students' mathematical justifications for solving derivative problems collaboratively, especially before and after the use of technology was allowed. We asked two undergraduate students who were preservice mathematics teachers in a paired…