Inspection criteria for schools with a religious character in England and Wales require the sponsoring body to arrange assessment on aspects of the distinctiveness of the school ethos. The Student Voice Project was designed to include year-five and year-six students in this process. Within the Diocese of Llandaff, the Diocesan Director of Education utilised the customised reports prepared at the end of the first year of the survey for schools participating in the project with the senior leadership teams in order to enhance school improvement and effectiveness. The present study compares the responses of the 1,192 students participating in year one of the survey with the responses of the 1,111 students from the same 23 schools participating in year two. These data show a significant overall increase in scores recorded on the six-item scales designed to measure student attitude towards five areas of ethos (school character, school experience, school teachers, relationships in school, and school and environment). These findings suggest that the Student Voice Project, effectively implemented by the Diocesan Director of Education, had significant impact on the participating schools. Similar impact was not found, however, in the control group of students from 41 schools within four other dioceses.