This project aimed 1) to investigate the change of vocal function in teachers over time with voice intervention provided and 2) to compare the self-perceived quality of life (QoL) between the practicing teachers and student teachers. The project consisted of two prospective studies, in which practicing teachers (study 1) and student teachers (study 2) were recruited as subjects respectively. In study 1, the subjects were randomly assigned to two groups: voice training group and no-training group. In study 2, the subjects were randomly assigned to three groups: vocal hygiene (VH) group, vocal hygiene and voicing technique training (VHT) group, and no-training group. Participants in the intervention groups were invited to attend the corresponding training workshops respectively. In both studies, results demonstrated no significant positive change of vocal function in subjects after intervention provided. Also, no significant difference was found between the practicing teachers and student teachers on the self-perceived QoL. These findings did not support the hypotheses that 1) interventions with vocal hygiene education would lead to significant positive change in vocal function, and 2) the student teachers would have a better self-perceived QoL than the practicing teachers.published_or_final_versionSpeech and Hearing SciencesBachelorBachelor of Science in Speech and Hearing Science