A report on Tuesday by the Organisation for Economic Co-operation and Development (OECD) named Spain as one of the few advanced countries where public school teachers are not evaluated regularly after entering the field.
Though teachers in Spain must be assessed in order to enter the profession, there are no regular checks after they qualify.
"Monitoring and appraising teachers is central to improving schools," the report states. "If well-designed, teacher appraisal and feedback systems can be used as tools to increase the focus on instruction and teachers' professional learning."
Teacher evaluations are required in three-quarters of the 37 countries in the report. Of the countries that implement some checks on teachers, just Spain, Ireland, Israel and Italy do not require assessments on a regular basis.
"Regular teacher appraisals are most often used to inform decisions about further training," the report states. "In Spain, teachers in public schools (around 70 percent of the total teacher workforce) are appraised to access the profession but not regularly afterwards."
In most of the other countries, these assessments have an impact on teachers' futures, such as their pay or whether further training is needed, but "this is not the case for Spain," the report states.
"In Spain, the only consequence of underperformance noted in an appraisal is the failure to progress to registered or certified teacher status," the report states.
The report also revealed other aspects of the state of education in Spain. The country has a high enrollment rate of young children in early childhood education programmes, with 97 percent of three-, four- and five-year-olds enrolled in such schools.
Spain also has a slightly higher rate of students completing post-secondary education at 35 percent compared to the OECD average of 34 percent.
But Spain's still recovering economic state has perhaps held it back as well, the report reveals. One in four Spanish youth are neither working nor studying - one of the highest rates across the OECD countries.
And Spain spends just 4.3 percent of its GDP on education, compared to the OECD average of 5.2 percent.