Because of the large amount of students in the college computer general kinds of experimental class , it is hard to take a overall effective check on work attendance and will occupy much tutoring time, which will make many students' problems not get timely answer, influence the teaching effect. The author designs software to make each computer of the laboratory have a roll machine function, which is equivalent to install a virtual roll machine. We can accurately record the time for each student to come to the class and leave from the class, and form a detailed work attendance record. The software promotes the teaching indirectly and improves the teaching effect.