The study placed a particular emphasis on the so called data mining algorithms, but focuses the bulk of attention on the C4.5 algorithm. Each educational institution, in general, aims to present a high quality of education. This depends upon predicting the students with poor results prior they entering in to final examination. Data mining techniques give many tasks that could be used to investigate the students' performance. The main objective of this paper is to build a classification model that can be used to improve the students' academic records in Faculty of Mathematical Science and Statistics. This model has been done using the C4.5 algorithm as it is a well-known, commonly used data mining technique. The importance of this study is that predicting student performance is useful in many different settings. Data from the previous students' academic records in the faculty have been used to illustrate the considered algorithm in order to build our classification model.