 Using a unique French administrative dataset matching Junior and Senior high school teachers to their individual students, we provide new evidence on the relationship between teacher evaluation grades and teacher effectiveness. We analyze three evaluation grades: the certification grade, designed to assess teacher content-knowledge; the pedagogical grade, designed to assess teacher pedagogical skills and the administrative grade, designed to assess teacher administrative skills. We run "horse races'' to test the relative strength of these evaluation grades' relationships to teacher effectiveness. Exploiting within student, across topics variations in teachers, we find that, in Junior high school, the pedagogical grade is significantly associated with student achievement gains, even conditional on the certification grade. Low-income students are more sensitive to the pedagogical grade than others. We also find that, in Senior high school, the certification grade is significantly associated with student achievement gains, even conditional on the pedagogical grade. We further develop our analysis by studying, for Senior high school, the relationship between teacher evaluation grades and student achievement gains via teacher value-added estimates. This alternative empirical approach confirms our main result for Senior high school. Finally, we find that, even though it is statistically significant, the contribution of content-knowledge to teacher value-added remains smaller than the contribution of the first years of teaching experience. More precisely,  the effect of the first year of teaching experience on student achievement is equivalent to a 4 standard deviation increase in the certification grade.