This study utilized sensors to investigate how females and males might perform and reflect differently on their tennis skills in a beginner class. A quasi-experimental design was conducted in this study to investigate the learning outcome of using tennis sensors. Two classes of students enrolled in a college physical education course participated in this study. One class of the students, who applied tennis sensor and reflective strategy, served as the experimental group; the other class using traditional instructional method served as the control group. The end-of-semester achievement test results showed that students in the experimental group performed as well as those in the control group. However, the experimental group performed a relatively smooth swing pattern and had better sensor-collected shot-data scores than those of the control group. As to gender effects, female students benefited more from using sensors when learning backhand groundstrokes, as compared to those not using. Male students tended to perform better on timing, swing speed, and spin level on making shots than those of the female students. The most common skill problems for both genders were maintaining balance and shifting the center of gravity of the body while hitting the balls. While viewing their own filmed practice videos, both gender of students reflected mostly on the key tennis techniques taught in the class; however, additionally, male students were more likely to refer to expectations or emotions regarding to their performance but the female students tended not. This study also showed that the sensors could be a useful tool in facilitating the analysis of tennis beginners' performance and in assisting their learning of key techniques. Future studies should use the sensors to collect data from a large sample of tennis beginning players so that the differences between genders could be thoroughly examined and analyzed. In addition, how to improve the instructional approach while using sensors in class to better fit both male and female students' needs is another critical issue in this field. [For the complete proceedings, see ED579282.]