NAIROBI, Kenya – Maureen Akinyi is 14, serious and poised, and she dreams of becoming a lawyer. Orphaned at 3 after both her parents died of long illnesses, she’s lived with a succession of guardians, holding on to little except her clothes and her schoolbooks.

Job Onyando, 12, is a good-natured boy with a stubborn streak who’s had to hold his family together through his mother’s death and his father’s bout with alcoholism. He’s up before dawn every day to look over his homework and, when there’s enough food, to help prepare a meager breakfast with his three siblings.

Both children of Nairobi’s sprawling Kibera slum, scarred by Africa’s twin scourges of poverty and disease, have at least one thing going for them: They’re going to school.

A few years ago, that would have been unthinkable. But over the past decade, bowing to domestic pressures and backed by donors, several African countries have eliminated primary school tuition, paving the way for millions of children from poor families to attend classes for the first time.

In Kenya, one of President Mwai Kibaki’s first moves upon taking office in 2003 was to make education free through the eighth grade. Fees had started at about $12 a year per student, but that was too much for many poor families. When the fees were eliminated, students flooded into public schools. Enrollment rose to 7.6 million from 5.9 million, and it’s still climbing.

But the cash-strapped government still hasn’t hired more teachers or built additional classroom space. In cities such as Nairobi, classes bulge with nearly 100 students, and books and basic supplies often don’t reach remote regions.

Throughout Africa, there’s a catch to free primary education: It offers hope to the most vulnerable children, but it’s stretching school systems to the breaking point.

“It’s had an undisputed impact in helping children access school,” said Janice Dolan, an education adviser for the British charity organization Save the Children. “But at some level, the focus has been on access rather than quality of education.”

The first African nation to abolish school fees was tiny, impoverished Malawi, but 12 years later, its classrooms are still overflowing. The literacy rate has grown only 2 percentage points, to 60 percent. In a report on primary education this year, World Bank analysts singled out Malawi, Kenya and Uganda as countries where rapid expansion has degraded the quality of schooling.

“We are receiving children, and we are not ready for them,” said Elisheba Khayeri, the head teacher at Nairobi’s Ayani Primary School. “No one prepared us for these large classrooms.”

“Enrollment is up and the dropout rate is down,” she said. “More children are accessing school. Education in Kenya is now not only for those who can afford it.”

Kenya’s senior deputy director of education, Stephen Karaba, said the shortcomings were due to budget constraints and would eventually be addressed. He said the government is already spending roughly an additional $114 million each year – one-tenth of the total education budget – on free primary education, including textbooks for every student.

“While it is true that in the majority of schools, the children are more than teachers can handle effectively, teaching and learning materials are available for everyone,” Karaba said.