Others come to school too hungry, sick MB-300 dumps or exhausted from work or household tasks to benefit from their lessons. The consequences are grave: An estimated 617 million children and adolescents around the world are unable to reach minimum proficiency levels in reading and mathematics, even though two thirds of them are in school. This learning crisis is the greatest global challenge to preparing children and adolescents for life, work and active citizenship. Schooling does not always lead to learning. Worldwide, there are more non-learners in school than out of school. What’s more, 11 per cent of primary-school-aged children and 20 per cent of lower-secondary-aged children are not in school at all. Children and adolescents are excluded from education for many reasons.