We have proposed an introductory C programming exercise based on contest style using execution test series. We have developed a contest management server tProgrEss and have carried out educational practices since 2009. We developed an Instruction support tool vRoundEd in classroom round during a contest. The tool is for teaching assistants with each tablet PC. It shows a seat map in classroom and indicates progress information of the contest in each student. When an assistant notices a signal from a student in the seat map, he goes to the desk to help or uses a chat system. We revised GUI and extended several functions in the tool. We carried out questionnaires for more than 10 assistants. We consider the replies and opinions for improvement.