LILONGWE ? American pop queen Madonna broke ground Monday on a girls academy she is building in Malawi, billed as a "gift" to the country where she has adopted two children.

The 51-year-old star cut a cake, planted a tree and turned the sod alongside her eldest daughter Lourdes, 13, at a colorful ceremony attended by about 500 locals on the outskirts of Malawi's administrative capital Lilongwe.

According to a brochure for the Raising Malawi Girls Academy, the school will be a "leadership institution to prepare future women leaders" with 500 boarders including two impoverished girls from the country's 28 districts.

It will "focus on mathematics and science which traditionally have failed in Malawi and elsewhere", the brochure said.

Madonna's school is modelled on a similar academy built by US television talk show host Oprah Winfrey.

In 2006, the chart-topping musician adopted a baby boy, David Banda, who is now three-years-old. She returned to Malawi this year to adopt a girl, Mercy James.

Madonna is also funding several charities in the small southern African country, including homes for children with AIDS.

Construction of the academy will take two years.