For centuries, people have needed to share their thoughts. For this purpose, they tried to fulfill these needs both orally and in writing, thus the concept of communication appeared. Communication is the whole of the relational activities which are the condition for human beings to produce and develop their existence (Sur, 2015). In today's world, the concept of communication, with both technological and social changes, is discussed in many contexts. It is seen that the common ground in each communication method is ‘language’.

 Language is also important in the area of education. It can be said that there is a relationship between education and communication when it is considered that the teacher interacts with the students and the students interact among themselves in the classroom environments where the education is carried out.

 Moreover, the importance of language in teaching and learning mathematics is one of the prominent topics in mathematics education literature. In 2007, Boulet asked mathematics teachers to make the definition of polygon mathematically within a certain period of time and observed that teachers had difficulties. They said that they knew the definition but had difficulty in explaining it. It is the use of language that limits the students.

 Mathematical language is an element that enables students to understand the concepts and support them to establish a relationship between concepts (Akarsu, 2013). Especially in algebra it is important to use mathematical language correctly in order to support students' conceptual learning in an area which is generally considered to be a symbolic use. Since 1990, studies on the importance of the language used in mathematics have been increasing. Studies indicate that mathematical language plays an important role in supporting students' conceptual development (Boulet, 2007).

Furthermore, the algebra learning is the introduction to express mathematics in symbols. Algebra is considered to be abstract and theoretical, although it is almost always in the daily life of students. Teachers focus on especially symbols in this field. But the use of these symbols without learning the meaning will create situations that will adversely affect the conceptual learning of the students. After correct conceptual learning is provided, students are expected to explain the symbols and symbolize mathematical expressions easily. Studies indicate that the correct use of mathematical language will play a supporting role in conceptual development of students (Boulet, 2007).

 Lesh (1981) states that there are some processes to go through in order for a mathematical concept to be understood. These processes are real world situations, spoken symbols, manipulative models, written symbols and pictures. Based on Lesh’s this study four sub-dimensions of mathematical language have been developed. These are real world situations, using written formal language, verbal expression and graphic and figure expression. In this study, it is aimed to look at the students' ability to go through these processes in the field of algebra learning and their transformation into each other.

The aim of this study is to examine skills of middle school students to use mathematical language in the field of algebra learning. The study will be designed as a case study, one of the qualitative research methods. Participants of the study will be secondary school students in two public schools in Keçiren, Ankara.  The data will be obtained by interviews. As a data collection tool, a 26-item test will be constructed by the researcher with the help of relevant literature review. To analyze the data collected, content analysis is going to be used.

The study will be designed as a case study, one of the qualitative research methods. Deep examination and description of a limited system is called case study (Merriam, 2013). Yin (2008) defined the case study as "An empirical inquiry that investigates a contemporary phenomenon within its real-life context, especially when the boundaries between phenomenon and context are not clearly evident". Participants of the study will be middle school students in two public schools in Keçiören, Ankara. The data will be obtained by interviews. The mathematical language competences of the students will be investigated with the scale which is prepared by the researcher by the help of relevant literature review and will be given to the students for the determined purpose. In this context, sub-problems will be developed in the process. To analyze the data collected, content analysis is going to be used. The answers of the students will be examined according to the determined branches of the mathematical language and algebra learning domain, and themes will be created especially for the parts which are considered possible for making a mistake. Answers will be tried to match with these themes. The questions in the interview form were created by using various sources in the literature. The first of these sources is Chelsea Diagnostic Algebra Test (CDAT). This test was developed by the Secondary Education Math and Science Team (CSMST) (Hart, Brown, Kerslake, Küchemann and Ruddock, 1985; 1998) to determine the algebraic thinking levels of British children aged 13-15 and to measure the conceptual knowledge of algebra (Akkus, 2004). The entire test was adapted to Turkish by Akkuş (2004). Another source used in this study is one of the measurement tools used by Akkus (2004). It is a representation inventory which involves 15 questions. The Algebraic Thinking Levels Test used in the study of Altun (2005) is the other source used. Finally, the 17th question in the form was taken from TIMMS 2011 exam. TIMMS is a survey study to evaluate the knowledge and skills acquired by students in mathematics and science. For the validity and reliability of the research, determined questions will be readjusted after offering for consideration of a few specialist and pilot scheme, the themes and the answers matched by the researcher will be reviewed with the help of a specialist. In addition, the responses in the interviews will be described as direct quotations through the sound recordings.

The present study has not been concluded yet but it is expected that students will not be able to use mathematical language in the field of algebra learning. It is expected that students will not be able to use the mathematical language appropriately in the questions that should be expressed in tables and graphics. The responses of the students are expected to be matched according to the determined branches of the mathematical language and the themes created according to the field of algebra learning.It is expected that the findings of this study on the use of mathematical language in algebra learning will contribute to the field both scientifically and practically.

Akarsu, E. (2013). Examining seventh grade students’ use of mathematical language in algebra learning area. Unpublished Master Thesis, Dokuz Eylül University, İzmir. Boulet,G.(2007). How does language impact the learning of mathematics? Let me count the ways. Journal of Teaching and Learning,5(1). Lesh, R. (1981). Applied mathematical problem solving. Educational Studies in Mathematics, 12(2),235-264. Sür, B. (2015). Investigating the reflections of mathematical elements to written and oral mathematical communication in the context of 9th grade triangles subject. Unpublished Master Thesis, Marmara University, İstanbul.