We study the existence of a gender gap between two methods of grading student achievement in Spain, namely teachers' assessment which measures cognitive outcomes and standardised test scores, which are consistent across Spanish schools. We use rich census information of Andalusian students attending secondary schools. Our results indicate that overall teachers' assessment favours girls compared to the result of standardised test scores in reading and maths. On average, girls obtain 0.35 points more than boys in teacher's assessment on a 1 to 10 scale (0.15 SD), conditional on both having the same competencies. Additionally, we have found that the gender gap is stable across different levels of students' own ability and peers' ability. These results are robust to a set of census social characteristics. The presence of grading disparities suggests that test scores could complement teachers' assessment; specifically, they could be used to inform about the gender gap in assessments.