This study is a qualitative case study research, determining the purposes of teachers to use the eTwinning platform and to examine the effects of the platform on teachers. The study group consisted of 15 volunteer teachers who carried out eTwinning projects rewarded with quality labels. In the study, the data were obtained through a semi-structured interview form, and the content analysis method was used in the data analysis. According to the results obtained, it was concluded that teachers used the eTwinning platform in order to make projects, participate in online courses, contribute to their professional development and collaborate. The platform has a great contribution to teachers both personally and professionally. As a result, it is obvious that the eTwinning platform is very useful for teachers. The platform is so effective that it contributes to the professional and personal development of teachers, and even changes their perspective on the profession.

Integral transforms provide us great convenience in finding exact and approximate solutions of many mathematical physics and engineering problems such as signals, wave equation, heat conduction, heat transfer. In this study, we consider the Kashuri Fundo transform, which is one of these integral transforms, and our aim is to show that this transform is an effective method in solving steady heat transfer problems and obtained results are compared with the results of the existing techniques.

Turkey experiences distance education at the master’s and doctorate degrees for the first time. This study aims to reveal the essence of the distance education experiences of mathematics teachers who continue their postgraduate education with distance education due to the COVID-19 pandemic. This study was carried out using the phenomenological research design with six mathematics teachers who continue their postgraduate education at a state university in the Central Anatolia Region in the 2019-2020 academic year. Of the participants selected by the criterion sampling, three were master’s degree students and three were doctoral degree students. Research data were collected using semi-structured interview forms designed in line with expert opinions. The interviews were conducted online via video call on the WhatsApp application due to the COVID-19 pandemic. The experiences of the participants were identified with the phenomenon of “solo pantomime”. Participants had positive experiences such as easy access, possibility of review, improvement in technological pedagogical content knowledge, and negative experiences such as communication and connection problems, the irregularity in the schedule, inadequacy of the lesson hours, and focusing problems regarding synchronized distance education. Distance graduate education is also considered quite suitable for mathematics education courses, but insufficient for mathematics field courses. It is also understood that some participants had plans to make radical changes in their thesis topics. Participants avoid long-term experimental studies or studies that can be conducted with a large sample, and they tend towards studies that can be carried out with document analysis or small groups and had problems with their supervisors.

No abstract

Number sense is one of the topics studied by mathematics educators and researchers in recent years, and its importance is emphasized. The number of studies on number sense in our country is increasing day by day. The content analysis of these studies is thought to be a guiding guiding for teachers, mathematics educators and researchers and a guide for future studies. Therefore, the purpose of this study is to determine the tendency of number sense studies published in the field of mathematics education published as an article between 2011-2020 in Turkey. With this purpose 50 articles that meeting the specified criteria have been examined. In the analysis of the data, the "Article Review Form" was used and analyzed with content analysis, presented in tables with frequencies and percentages and interpreted in the light of this information. According to the findings of the research, it has been determined that the most of studies for number sense quantitative studies that using descriptive survey method. It was concluded that the target group of the studies was mostly aimed at primary school 5-8 students and the topic was studied with more than 100 samples. It was determined that the most that scale as a data collection tool and quantitative data analysis methods were used as a data analysis type. When the studies were examined according to the tendency of the topic, it was concluded that the studies focused on understanding the number sense more deeply and to measure the number sense.