The work aims to develop a gesture interaction application that meets user needs, and propose a gesture-function mapping model based on experience design with classroom scenarios as an example. The HTA model was used to establish connections between user needs, software operations, and corresponding gestures, to obtain teachers' software usage needs and expectations in the classroom through shadow tracking and in-depth interviews, and transform them into design principles. Intentional gestures of subjects were obtained through Wizard of Oz experiments, and characteristic gestures were extracted according to usage frequency, cleaned, and processed according to design principles. The mapping relationship between gesture actions and functional definitions was implemented through open-source frameworks such as OpenCV, Tkinter, Pyautogui, etc. Finally, usability testing was conducted through experiments to verify its effectiveness. The gesture mapping for six functions was established. In the classroom scenario, three optimization directions for data enhancement were discovered. In conclusion, the gesture mapping model, which combines user behavior and attitude research, can effectively improve the usability of gesture interaction, providing a reference for gesture interaction designers and developers based on scenario-based gesture interaction paths.