The aim is to get all children worldwide into school

The Global Campaign for Education (GCE) estimates that 100 million children worldwide miss out on schooling.

Children in 105 countries, from the US to Bangladesh, are taking part in a week of awareness raising.

The UK's International Development Secretary, Hilary Benn, pledged �12m to help provide an education for the world's poorest children.

He and Education Secretary Charles Clarke were among the senior MPs talking to 700 children who lobbied Westminster on Tuesday.

The week of events in the UK will culminate on Friday with over 400 MPs going back to school for the day.

Education for all

Hundreds of children in the UK lobbied MPs

The GCE action is taking place four years after 182 governments, including the UK, signed the "Education for All" commitment in Dakar, Senegal.

The aim is to ensure primary education for all by 2015 and equal enrolment for girls and boys in primary and secondary education by 2005.

At the current rate of progress, the GCE says both these targets will be missed and it will be 150 years before all the world's children have the opportunity to go to school, with children in Africa having to wait the longest.

School is full

It is hoped children like 12-year-old Adiatou Issaka from Niger will benefit from the campaign.

Although Adiatou lives just 500 metres away from a school, she cannot attend as it is full. There is only one classroom built from straw and one teacher for 59 children.

Teachers are in short supply in many countries

"Sometimes my little brother asks me to go to school with him but I have to say no," she said.

"My brother wants to be a teacher so he can share knowledge with everyone. I want to learn to read and write too."

United Nations Secretary general Kofi Annan said: "Over 100 million children are being denied a basic human right - the right to an education, and most of those missing out are girls.