They said teachers could remind themselves that not all children are at the same stage by taking steps like calling the register in birth order rather than alphabetically and grouping children together by age.

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"The petition calls on Pakistan to ensure that every girl like Malala has the chance to go to school, " he said, while also calling on the international community to ensure all children have access to education by the end of 2015.

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The Campaign has collected 18 million signatures calling on world leaders to ensure that all children are in school by 2015.

UNESCO: Post-Conflict and Post-Disaster Responses