This study reports a small part of a large-scale study. In this vein, trends in cognitive demand levels of mathematical tasks in the Algebra Learning Domain of 5 mathematics textbooks prepared according to four middle school mathematics curricula that have been updated since the beginning of the 2000s in Turkey were determined. This study is a…

This study examines middle school mathematics teachers' concept definitions of five geometric objects (prism, pyramid, cone, cylinder, and sphere). The study included 99 middle-grade mathematics teachers in three provinces and districts. The data were gathered through six open-ended questions determined to reveal the participants' Concept…

This study investigated how pre-service middle school mathematics teachers attend, interpret, and respond to the students' thinking about statistical concepts in a case-based teacher training environment. 25 pre-service middle school mathematics teachers participated in the study, and they were asked to make evaluations on the cases given. Based…

This study aims to compare two different learning environments designed online in terms of their contributions to the development of mathematical modelling competencies. In the research, which was designed with the triangulation method, among the mixed research methods in which the qualitative and quantitative research methods are used together.…

Measures of center have a central role in statistics education. There, however, is not much research on textbook analysis on measures of center, especially at the international level, which is crucial to keep up with the changes in a data-driven globalised world. This study aimed to investigate how selected school mathematics textbooks of…

There exist many studies on modeling competencies and their promotion; however, there is a need to investigate what modeling competencies are and how they vary in lower and higher-achieving groups of students in mathematics within the current modeling literature domain. This study examined how mathematical modeling competencies were displayed in…

This study investigates prospective secondary school mathematics teachers' developing conceptions about the meaning of derivative (as rate of change) while working on a series of tasks involving different non-motion real-life contexts. The study was conducted by employing a case study method. The participants of the study were 25 prospective…

This study investigates the development of prospective secondary mathematics teachers' (PSMTs') noticing skills in a course conducted at the last year of their teacher education program. PSMTs watched and analysed different instructional videos, including an unknown teacher's, their mentor teacher's, and their own teaching videos. The data were…

This qualitative research presents how a mathematics teacher educator's feedbacks to two lower secondary school mathematics teachers affects their design of hypothetical learning trajectories regarding teaching patterns and their teaching practice. The data comes from a web portal, which was designed as a professional development tool for…

The purpose of this study was to investigate secondary mathematics teachers' conceptions of the barriers to the development of mathematical literacy. The data were collected through semi-structured interviews with sixteen in-service mathematics teachers from nine secondary schools of five different school types. The data analysis consisted of an…

This study investigates how a sample of middle school mathematics teachers interpret and use compulsory textbooks in the Turkish classroom context based on their: (i) purposes of using textbooks; (ii) frequency and duration of using textbooks; (iii) approaches to using textbooks; and (iv) preferences concerning an ideal mathematics textbook. The…

Although students' nonstandard strategies have great importance in understanding students' thinking and creating effective mathematics classrooms, much remains unexplored in the literature. This study investigated 22 middle school teachers' reasoning about a student's nonstandard strategy for the division of fractions. The data were collected…

The purpose of the current article is to test and revise the hypothetical learning trajectory designed for teaching quadrilaterals by reporting the classroom mathematical practices emerged in a social learning environment developing preservice middle school mathematics teachers' understanding of quadrilaterals. Ten preservice teachers participated…

The purpose of the study was to investigate the effects of mathematics instruction supported by dynamic geometry activities on seventh grade students' achievements in the area of quadrilaterals, based on their van Hiele geometric thinking levels. The study followed a nonrandomized control group pretest and posttest research design. Participants of…

The purpose of this study was to investigate eighth grade students' skills in different problem-posing situations. Problem-posing situations include free, semi-structured and structured problem-posing situations. The study was conducted using case study methodology, which is within the scope of descriptive research. The study was conducted with…