As mothers have poured into the workplace over the last decade, they've learned to squeeze parent-teacher conferences into their lunch hours and help children with homework between dinner-fixing and laundry-sorting. And they've taken some comfort in the myriad of studies showing that their children's academic achievement scores compare favorably with those of children whose mothers are at home.
But working mothers should expect no such comfort from the United States Department of Education. There, a soft-spoken researcher has concluded that ''children from one-parent families, or children from two-parent families whose mothers work, tend to have lower academic achievement.''
So says Alan Ginsburg in a recent government study of 1976 and 1980 national data that's raising political, educational, and sociological hackles across the country.
Mr. Ginsburg, a quiet civil servant at the Education Department's Office of Planning, Budget, and Evaluation, and outside consultants Ann Milne and David Myers say their study ''proves'' that ''both elementary and secondary students living in two-parent homes show lower achievement if their mothers work.'' The study also notes that ''the magnitude of the effect is directly related to the amount of time mothers work.'' Achievement gaps are widest, the researchers say, betweeen the mother who has worked full time over a large period of the child's life and the mother who has stayed at home during that period.
The gaps - even though disputed - are being spotlighted at a time when the nation's attention is already trained on educational issues. The figures seem alarming: ''White high school students whose mothers worked full time from preschool through high school,'' says the study, pointing to its most severe example, ''score up to nine percentile points below those whose mothers never worked at all.''
This finding is in direct contradiction to other studies done to date, says Barbara Heyns, an educational researcher at the Russell Sage Foundation in New York, who studies maternal employment. ''Everything in the literature so far supports the conclusion that the mother working shows no effects on the child,'' she says, ''once you control for income.''
On the other hand, studies have consistently shown a correlation between income and achievement, she points out - the higher the family income, the higher the academic achievement. The Education Department's study simply shows the same effect, she says, demonstrating that the children of lower-income single mothers or poorer single-income families achieve lower results.
But Ginsburg, who finds the ''existing literature contradictory, at best,'' points out that ''in the few studies done recently on single parents,'' those that include income as a factor affecting the children's achievement ''don't recognize that the mother's marital status is behind the lower income. In other words, there may be more of an effect from being in a single-parent family than from having a lower income.''
The Education Department researchers believe that they did control for both income and socioeconomic background and still found lower achievements among those whose mothers worked full time. But they admit that the income controls had flaws: ''We might be comparing two families, each making $50,000,'' Ginsburg explains. ''In one family, maybe the father is a doctor or a lawyer and is making the whole $50,000 himself; in the other, you have two parents, each making $25,000. They're two very different families.'' An update of the study is expected to control for this factor.
The researchers also discovered inconsistencies in their conclusions. For example, children of single black women who worked full time did better in school achievement than children of unemployed black women, ''probably because if she's not working, she's on welfare,'' says Ginsburg.
Conservatives might be expected to interpret this study as proof that women should stay home. In particular, they will likely make hay out of the study's conclusion that in two-parent families ''where very low income is not an issue, mothers may positively affect their children's achievement through educationally oriented time in the home.''
The study precludes overly quick assumptions in these matters, however. ''There are indications that, in the case of these working mothers other changes are taking place which may mitigate the problems,'' it also concludes. ''Families are becoming smaller, women are seeking more part-time jobs, and fathers are assisting more with child care and other household duties.''
But such changes only go so far, says Ginsburg, pulling out a University of Michigan study of time allocation in the American family. The research shows fathers in families with working mothers spending a minuscule one minute per weekday teaching their children; when the mother is at home, the total drops to zero. This bodes ill, he thinks, for the education of children in this country.
''There are all sorts of implications you can read into this,'' says Ginsburg , sitting in his paper-strewn office. ''We certainly don't expect women to stop going to work because of this study. But we do expect there ?to be a shift, eventually, from people viewing this as a woman's problem to viewing it as a family problem.
''The family's still one of the most important educators,'' he concludes. ''All the literature proves that.''