Abstract This paper explores the application of interdisciplinary teaching in teaching numbers and arithmetic to Grade 4 students. Interdisciplinary teaching is an advanced pedagogical approach that provides students with a holistic perspective on knowledge and enhances their problem-solving skills. The paper analyzes the concepts, principles, types, and models of interdisciplinary teaching. Additionally, it examines the content, objectives, and methods of teaching numbers and arithmetic in Fourth-grade, highlighting the benefits of applying interdisciplinary teaching. Examples of integrated lesson designs suitable for teaching mathematics to primary school students are also provided. Keywords: Interdisciplinary teaching, numbers and arithmetic, Fourth-grade students.