Studies of educational inclusion have indicated pathways meant to ensure the inclusion of people with disabilities within regular schools. Nevertheless, little has been mentioned about the implications of circadian rhythm regarding the inclusion of totally blind students in school. This article aims to describe how the circadian rhythm might influence educational inclusion of students with visual impairments. Based on a review of the literature, we present the main concepts of chronobiology-the science that studies the ability of living organisms to express their behavior and physiology recurrently over time. One of these expressions-known as the circadian rhythm-lasts for a period of 24 hours. This rhythm is regulated by a person's biological clock which is in turn regulated by daylight. However, in the absence of light, which is the case for those who are totally blind, it is up to the biological clock to regulate circadian rhythms. In this condition, known as free course, people who are totally blind may present reduced academic performance from time to time due to excessive drowsiness during study hours, not to speak of mood disturbances, lack of alertness and attention. Given such a context, this information should be divulged in order for conditions of attention deficit disorder, irritability, social isolation and/or drowsiness during daytime resulting from free course to be recognized, so as to respect the individual needs of students who are totally blind, ensuring them full access to educational inclusion.194519530Amaral, L.A., Sobre crocodilos e avestruzes: Falando de diferenças físicas, preconceitos e sua superação (1998) Diferenças e preconceito na escola, pp. 11-30. , In: AQUIN O, J. G. (Org.)., alternativas teóricas e práticas. São Paulo: SummusAranha, M.S.F., Inclusão social e municipalização (2000) Educação especial, pp. 1-9. , In: MANZINI, E. J. (Org.).,: temas atuais. 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