The National Institute of Education (NIE) has undertaken two major reviews of the research it is sponsoring and reached a conclusion that ought to warm the heart of working mothers: Their children do as well in school as the children of mothers who stay at home.

In fact, the research is showing that the children of working mothers who are professionals, low-income, or black do better in school than their peers whose mothers stay at home--although it is not known why.

These findings were released Friday at a conference in Washington sponsored by the Home and School Institute, which stresses ways children can learn at home. The conference focused on ways schools and other institutions in a community can help children from single-parent homes, most of which are headed by working mothers.

Early studies of children from single-parent families found they performed less well in school. Dr. Oliver Moles of NIE said these earlier studies did not consider the different socio-economic status of the children studied, so that children from poor educational and income backgrounds were compared with children from more enriched homes.

The findings have now been contradicted by some 15 to 20 more studies sponsored by NIE, which find the intellectual functioning and long-term development of children from single parents and two-parent homes quite similar.

The latest studies do show, however, that children from single-parent homes, particularly in the two- or three-year period around a divorce, tend to have lower grades, are more disruptive and have poorer attendance records.

Moles said these children face certain stressful changes in their lives that may affect how they function in school. "We know there is a serious economic decline in families when the father leaves," said Mowles. "This has a serious impact."

Mothers involved in divorce often have to go to work, which creates for preschool children, at least, the double loss of both father and mother. The family may also have to move to a less expensive home and neighborhood that may not be as safe, and the children may have to change schools and leave friends. The parents may be bitter, they may be busier than before, the child may be preoccupied in school or come to school late because of disruptions at home.

Dorothy Rich, president of the Home and School Institute, cited a National Academy of Science study of working mothers that concluded that one cannot approach the question of whether working mothers are good or bad for the children. "It depends," she said. "on the parents, the child and so forth. Arrangements appear to be the key element. Can you arrange your life so you can survive on the job, can you find some time to spend with the kids. What we are finding is the people who are the better organizers can find the time."

The studies shows that working mothers find time for their children by forgoing more demanding jobs, working part time, and eliminating personal leisure time. Working mothers, according to the studies, spend almost as much time caring for their children as nonworking mothers. The studies also found that most fathers do not spend more time in family care when their wives work, although well-educated, upper-income fathers do help out more.

The mother's work environment also appears to have significant impact on her family. A pathfinding study done in Austin, Tex., found that mothers in jobs with little autonomy, who were rigidly supervised and who had inflexible leave policies for such things as school appointments and children's illnesses, experienced greater stress and conflict in their families and greater doubts about how well they were doing as parents. "Employers and personnel managers, as well as union officials and labor activists, need to recognize the importance" to families of workplace policies. The study recommended more flexibility in the workplace and in school appointment policies.

The similarity of the school performance of children of working and nonworking mothers "runs against many people's notions about mothers working," Rich said. There is good news here for single and for working parents. But at the same time studies are showing more and more clearly that not all jobs are equally suited for working mothers. Guidelines are emerging that will help working mother evaluate not only what employers can do for them, but what their employment policies do for their children.