The computer can be a wonderful research and communication device, but just how disadvantaged are children whose families are too poor to provide one at home? Some economists have been studying the question and their findings may surprise you. Then again, they may not.

Writing from Silicon Valley business professor Randall Stross describes the research. In Romania recently the government invited low-income families to apply for vouchers worth 200 euros that could be used for buying a home computer. Two American economists studied those who qualified and those who, despite wanting a computer as much as the others and often having incomes only slightly higher, missed out on a voucher.

In a draft of an article that the Quarterly Journal of Economics will publish early next year, the professors report finding “strong evidence that children in households who won a voucher received significantly lower school grades in math, English and Romanian.” The principal positive effect on the students was improved computer skills.

They do say that, at the time of the programme, most Romanian families were not connected to the internet. That would have ruled out using the computer for research. How else would they have used them for homework -- just producing a neat essay with the help of a spell-check? Evidently it was not a question that bothered the kids; they used the machines daily to play games.

A study in North Carolina found something similar. The arrival of broadband in the state between 2000 and 2005 was followed by lower test scores in maths and reading -- but this effect was largely confined to lower-income (black) households.

Third example: the state of Texas conducted a four-year experiment in “technology immersion” in which students at 21 middle schools were allocated laptops and allowed to take them home. The results were mixed and included lower scores for writing among students at the “immersed” schools.

THE one area where the students from lower-income families in the immersion program closed the gap with higher-income students was the same one identified in the Romanian study: computer skills.

Catherine Maloney, director of the Texas center, said the schools did their best to mandate that the computers would be used strictly for educational purposes. Most schools configured the machines to block e-mail, chat, games and Web sites reached by searching on objectionable key words. The key-word blocks worked fine for English-language sites but not for Spanish ones. “Kids were adept at getting around the blocks,” she said.

How disappointing to read in the Texas study that “there was no evidence linking technology immersion with student self-directed learning or their general satisfaction with schoolwork.”

Conclusion? Technology is not the answer to the educational achievement gap between socio-economic groups; in fact it can widen the gap. With or without computers, kids will fritter away homework time entertaining themselves unless they have parents keeping an eye on them and giving a hand when required.

This is the great gap between children -- the parental divide, not the digital divide.