A computer game paradigm is used to train trainees in the skill of packing shopping bags. A number of items appearing on a conveyor in the computer game are packed into one or more bags in accordance with user input gestures of the trainee using graphical user interface techniques. The trainee is able to rotate items to make them fit within a bag in relation to positions of other items already within the bag. In addition, the trainee is able to move items within the bag to occupy different positions within the lateral boundaries of the bag. The computer game can be served through a computer network, such as the Internet or a LAN, as an applet or otherwise active web page. Accordingly, the trainee can practice or completely self-teach the skills of bagging from the comfort and convenience of any computer connected to such a network.