Practical abilities are important for students from majors including Computer Science and Engineering, and Electrical Engineering. Along with the popularity of ACM International Collegiate Programming Contest (ACM/ICPC) and other programming contests, online judge (OJ) websites achieve rapid development, thus providing a new kind of programming practice, i.e. online practice. Due to fair and timely feedback results from OJ websites, online practice outperforms traditional programming practice. In order to promote students' practical abilities in programming and algorithm designing, this article presents a novel teaching idea, online judge & practice oriented teaching (OJPOT). OJPOT is applied to "Programming Foundation" course. OJPOT cultivates students' practical abilities through various kinds of programming practice, such as programming contests, online practice and course project. To verify the effectiveness of this novel teaching idea, this study conducts empirical research. The experimental results show that OJPOT works effectively in enhancing students' practical abilities compared with the traditional teaching idea.