Chenai Moyo, 18, is confident she would have passed the examinations at her school in Harare, Zimbabwe's capital, but for two years in a row there was no money; now she has to fend for the family and depends on an older man for support.
"I couldn't register for examinations last year  because my father had just passed away, and the little money that was there went towards his burial. My mother is not employed and now that she is ill the situation is worse for me and my brothers," Moyo told IRIN. Her mother tested positive for HIV in 2009.
Moyo was a brilliant student but said she would probably never sit her O-Level examinations, a school-leaving certificate. "My mother talked me into marrying this man, who is an elder in our church. He has promised to look after my ill mother and my two brothers, but I have given up hope of ever going to school again," she said.
She is not alone: recent education ministry statistics showed that some 100,000 learners (33 percent of those eligible to write O-level exams) and around 10,700 learners (29 percent of those eligible for A-level exams) had failed to register.
"This year ... there are a number of students out there who have failed [to register] because of poverty," education minister David Coltart said in a statement.
Zimbabwe's ailing education system, once a model for sub-Saharan Africa, has buckled and all but collapsed under the economic and political crises of the past decade, when widespread food shortages, hyperinflation, cholera outbreaks, and an almost year-long strike by teachers in 2008 led to a dramatic decline in the standard of learning.
It is not uncommon for 10 pupils to share a textbook, and although the government drastically slashed school fees in February 2009, deepening poverty put even the reduced cost of attending government schools in some areas beyond the reach of thousands of children.
The government extended the initial exam registration deadline of 28 May by two weeks, but most people were sceptical that parents and students who had previously been unable to pay the fees - US$10 per O-level subject and US$20 per A-level subject - would be able to raise the money in time.
"The extension means nothing at all - the period is too short, and one wonders why the government is in such a hurry to close the door on students," the president of the Progressive Teachers Union of Zimbabwe (PTUZ), Raymond Majongwe, told IRIN.
"Besides, late entrants will be fined US$5 per subject and we don't know where the government expects the poor parents that have failed to raise the examination fees to get the extra amount."
Majongwe said he thought the ministry's figure for the number of students who had failed to register for examinations was an "understatement" of the gravity of the situation.
"According to our own independent surveys, close to 200,000 O- and A-level students have been denied the chance to prepare for their future. There are thousands who have resigned themselves to fate, as they have failed to write in the past and are not part of the current statistics since they are not attending school," he pointed out.
A headmaster at a secondary school in Seke rural district, about 40km south of the capital, said only 30 students at his school would write their O-level examinations this year.
"I was supposed to have 125 students sitting for their O-level examinations but only a handful managed to register," he noted. "While the examinations fees might not seem too high, it should be remembered that the majority of households in rural areas still have large families to look after, and there is a significant number of child-headed families."
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