Modern mathematics plays a vital role in science, commerce and industry, because it is firstly considered a powerful, authentic and inspirational communication device and secondly, it is a tool for measurement and prediction. The power of mathematics lies in its signs (symbols) that include grammar and analysis, as well as its particular combinations. Mathematics can develop rational thinking and also enjoy an aesthetical attraction. Perhaps many people, and even teachers suppose that mathematics has been defined as the state of the art in computing and the responsibility of mathematicians is to spend their entire lifetime for making complex mathematical calculations. In this sense, such a belief is not sufficiently close to the truth. The core function of mathematicians is reasoning not calculation. In fact, the goal of teaching mathematical concepts is not to calculate; rather it is to develop the rational thinking of learners which is considered very important. The main purpose of this paper is to expand and develop an interest in mathematics as well as to strengthen motivation. In addition to mentioning the importance and necessity of learning math lessons in the elementary course, this paper seeks to present the principles of teaching mathematics in order to improve its teaching in this course.