Liberia, which elected a new president last week, has among the highest percentage of out-of-school primary children in the world.

Liberian ministers last year decided to transfer the management of 93 government schools to eight private operators - mostly international school groups, but also some homegrown operators.

These 93 schools remained state schools - with government teachers, open enrolment, and no fees.

Liberian ministers decided to do something else just as bold - they would support a rigorous, independent, evaluation of their own policy.

Alongside the 93 privately-managed government schools would be a similar number of government "control" schools, to test whether the private operators were genuinely doing better.

Instead of the government marking its own homework, researchers from the Center for Global Development in Washington DC and the University of California at San Diego oversaw a selected sample of 3,499 students in 185 schools.

The first year of "PSL" is now complete, and the results from the initial evaluation of the programme are in.

What do they show? For the supporters of the "Partnership Schools", there are some pretty impressive statistics.

Students in these schools made learning gains of more than half an extra year of schooling in English, and two thirds of an extra year in maths - versus the government schools.

Read the full article on Liberian schools by David Laws at BBC