Very low or no impact for very low cost, based on very limited evidence.
School uniform is the clothing pupils are required to wear at school. Uniforms vary from the very formal (requiring blazers) to more informal (involving just a school sweatshirt). Schools vary as to how strictly a uniform policy is enforced.
How effective is it?
There is a general belief in many countries that school uniform supports the development of a whole school ethos and therefore supports discipline and motivation. However, there is no robust evidence that introducing a school uniform will, by itself, improve academic performance, behaviour, or attendance. There are studies that show changes in these outcomes after the introduction of a school uniform policy. However, in these cases uniform was usually one factor amongst several improvement measures, such as changes in behaviour policy or other aspects teaching and learning. Therefore it is not possible to claim that changes in outcomes were caused by the introduction of a uniform.
There are cultural issues about how a school uniform is perceived which play an important role in determining its acceptability and pupils’ compliance. There is some evidence that free school uniforms improve attendance in areas of very high poverty, however this does not appear to be true in all cases. In some cultures, school uniforms are associated with regulation and the loss of individuality, so care must be taken when generalising from studies in different contexts.
Latin American evidence:
There is very limited evidence about the effect of school uniform on learning in Latin America and the Caribbean. A study about discrimination against indigenous bilingual migrants in Mexico, based on a qualitative study carried out in two schools, shows that when the uniform is dirty or incomplete it tends to generate segregation among students within the school. The severe lack of evidence not just in Latin American and the Caribbean, but also around the world, suggests that any implementation of this practice, aimed to improve outcomes, should be done with caution.
How secure is the evidence?
There are no systematic reviews or meta-analyses of well-controlled studies of school uniform policy. The evidence rests mainly on correlational studies that have compared the performance of schools with uniforms to those without, or that have examined a school's trajectory of improvement after the introduction of school uniform. One of the problems in interpreting this evidence is that schools in challenging circumstances often choose a school uniform policy as part of a broader range of improvement measures. The most rigorous reviews and analyses have so far been unable to establish a causal link, but speculate that adoption of a uniform policy may provide a symbolic and public commitment to school improvement.
What are the costs?
The costs for schools associated with introducing a school uniform are very low. Normally the costs are borne by parents who must buy the required clothes.
What should I consider?
Before you implement this strategy in your learning environment, consider the following:
Wearing a uniform is not, on its own, likely to improve learning, but can be successfully incorporated into a broader school improvement process which includes the development of a school ethos and the improvement of behaviour and discipline. If you are planning to implement a uniform policy, have you considered how you will embed it in a wider school policy which will improve learning?
There is a general belief that school uniform leads to improvements in pupils’ behavior. It is important to remember that improved behaviour, on its own, does not necessarily lead to better learning, though it may be an important precondition (see Behaviour interventions).
Staff commitment to upholding and enforcing a uniform policy is crucial to successful implementation.
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(*)Síntesis elaborada por SUMMA a partir de la revisión sistemática de investigaciones académicas realizadas en la región.