Mathematics contributes a great deal of the development and research of all disciplines and Arithmetic is the foundation of mathematical knowledge, commonly understood as the art of computation and its application. Fraction is one of the important concepts in arithmetic that has occupied a key position in the school curriculum. In the beginning years of the schooling, it is taught to provide competence in performing the fundamental operations with the numbers. Students tend to view fraction as isolated digits, treating the numerator and denominator as a separate entities that can be operated on independently and one of the major source of difficulty in students learning in fraction can be multiple meanings like part/whole, decimals, ratios, or quotients. Students understanding of fraction are very rote, limited and dependent on the representational form. So, diagnosis of their difficulties in fraction at primary stage can be benefited by taking care while teaching and by providing necessary remedy to them. Authors of this book tried to identify learning difficulties of upper primary school students in fractions and decimals and provided necessary suggestions.