The women sat in the cramped classroom following the text in their booklets while a volunteer teacher read slowly to them. The subject was religion, and how Muslims, Christians, Buddhists and those of other beliefs, should try and live happily together.
One of the women had dropped out of school when she was a girl because her father had not been able to afford the fees. Another had left school early because she had to look after her younger brothers and sisters. A third had had almost no education because the school was too far away from her home.
These women in Magetan a small town in eastern Java were all illiterate and struggling to learn to read and write. Millions of women all over the world find themselves in similar circumstances.
But all the research confirms the ancient saying that: "If you educate a man you educate a person, but if you educate a woman you educate a family."
Studies by the World Bank and others show that educating women reduces their risk of dying in childbirth, improves the chances that they and their families will grow up healthy, decreases the number of children they have, and increases their children's chances of doing well in school.
But teaching adults to be literate is difficult, according to Helen Abadzi, an educational psychologist with the World Bank. Adults need to make a great effort to learn to read, making comprehension an even greater task. Inexperienced adult readers therefore tend to avoid it and quickly lapse back into illiteracy.
Because of these difficulties, the World Bank reduced its support for literacy projects after a discouraging review in 1987, says Ms Abadzi, many governments had kept on asking for help.
The conference on Education for All in Thailand in 1990 revived the determination of many to keep going. The World Bank now finances, or is planning to finance, literacy campaigns in Ghana, Bangladesh, and Senegal as well as Indonesia.
But the Indonesians are facing a huge challenge. Their campaign is based on a series of illustrated booklets which are written in Bahasa Indonesian, a variant of Malay, the official national language, chosen to strengthen the unity of a country that sprawls over 13,000 islands where it is estimated that there are between 150 and 400 languages.
But how do you get women, usually exhausted from hard physical work in the fields or on construction sites, and having to look after their children, to sit in a class twice a week for two hours? Any free time they have they want to use to make extra cash.
The directorate of community education in Jakarta started granting small loans to some of the women so they could start businesses.
In return, the women had to agree not to drop out of class. A woman in a Javanese village called Kampong Ponggalan, for example, started a thriving business making emping (pancakes) as snacks with a US$30 loan. When not pounding and cooking, she laboured through the booklets.
Literacy campaigns can sometimes seem endless, but the Indonesians have certainly made progress. Statistics on literacy are notoriously difficult to pin down, but more than 90 per cent were believed to be illiterate at the time of independence from the Dutch in the late 1940s, when the population was 70 million.
Now the population is 185 million, and the percentage of those illiterate is estimated to be down to about 20 per cent, with 70 per cent of those being women.