When 8-year-old Jennie Frankel talks about her love affair with computers, it's hard to believe that she is a real third-grader from Potomac and not the star of a slick television commercial designed to get achievement-oriented parents to buy the latest educational software for their children.

As the daughter of Washingtonian magazine computer columnist Steven Frankel, Jennie lives in a high-tech world. There are no less than eight home computers at her disposal, as well as a stack of the latest programs, which she uses for everything from designing her own birthday invitations to studying her spelling words. She started doing arithmetic problems on the computer when she was 4. By the time she entered first grade two years later, she was working at a third-grade level.

Of the computer, Jennie says simply, "I like it a lot. It made my grades better because it's more fun. I couldn't stand this summer; I couldn't wait to get back to school. I think the computer did that. It taught me that it's fun to do things even though you're learning."

A growing number of youngsters like Jennie are using educational software at home to help them with their schoolwork. Although the jury is not yet in on whether it actually improves a youngster's grades, more and more parents seem to believe the hard sell, which warns that their children may fall behind without the latest electronic workbooks.

Families bought almost half of the $450 million in educational software sold in 1983, with the rest going to schools, according to a market survey by LaRuth Morrow of Stellar Solutions, a Richardson, Tex., consulting firm.

The best sellers were educational games like Math Blaster, which uses an arcade game format to drill basic arithmetic skills. Next on the list were simulation programs like Flight Simulator, followed by less flashy drill-and-practice programs and question-and-answer software such as the popular SAT preparation programs.

"Schools are in danger of being left out," warns Tom Ascik, senior associate at the National Institute of Education. Ascik organized a national conference on the home use of educational software last summer to examine the growing trend.

"I was told that parents don't trust schools. They see computer programs as insurance and compensation for bad instruction."

The home-based instruction is rooted in the traditional American value of individualism, says Ascik. "If parents have the discretionary money to buy the software , they don't have to ask anybody's permission. They just go and buy it. Americans are like that. It's marketplace-based."

A recent survey by the National School Boards Association found that most families with home computers use them principally for entertainment. Education, however, is a close second. Parents who buy educational software do so mainly to give their children a headstart on courses they will take later in school. Other parents use the software to expose their children to subjects not taught in their schools or to help with remedial work, according to the survey.

A few parents, like Mario Pagnoni, a Methuen, Mass., teacher, have even taken their children out of school to teach them at home with the help of the computer.

When Pagnoni's sons Joseph and James were in the second and fifth grades, he decided to take a leave of absence for a year and teach them at home. One of the first things they learned was how to type by using two popular programs, Typing Tutor II and Master Type.

Then his sons learned word processing and soon began writing papers on the family Apple II+. "The computer helped them write better," claims Pagnoni. "Before, the kids didn't want to rewrite much. Then they saw how easy it is to move paragraphs around. Now my sons write clear, uncluttered English."

Using Math Blaster and Word Attack, two arcade drill-and-practice programs, in addition to other software and traditional book instruction, Pagnoni says he helped his second-grader finish his grade's curriculum by November while his fifth-grader finished the year's work by December.

But Manfred Smith, a Columbia, Md., resident who teaches social studies at Takoma Park Junior High School, isn't so sure he wants his children to learn on the computer. Smith, 36, who teaches his daughter Jamie, 7, and son Jesse, 3, at home, says he isn't ready to give that much power to a machine.

"I have reservations about the computer. It's a very seductive piece of equipment. People say, 'Oh, marvelous. It will make you smarter.' I heard all those arguments about television. I've never seen a piece of technological equipment that will make people smarter."

Nationally, about half of the 5,000 readers who subscribe to the popular home-schooling newsletter, Growing Without Schooling, use the computer to help teach their children, reports editor Donna Richoux. Many parents, she adds, are reluctant to get a computer for their children.

"Some parents would rather have their kids get back to nature than learn how to program. We don't see the computer as being the end all and be all. We advise parents to use caution, and not to believe the hype the software producers give out. As long as people are cautious, it is a good development. A cheap computer is like a cheap typewriter. It's a useful tool."

Educators themselves are divided on the merits of computer-based instruction.

"Teachers will tell you anything that helps a kid learn is good," says Lawrence Fedewa, executive director of the National Education Association Educational Computer Service in Bethesda. "Traditionally, there have been two kinds of learning -- group or classwork and individual or homework. Computer homework is very helpful. But no one in their right mind would say that it is a substitute for what goes on in the classroom or group environment."

NIE's Ascik reports that research has found that computer-assisted instruction is at least as good and generally much faster than traditional instruction. But most of those studies have been done in the classroom, generally with older children. Little research has been done on the home use of educational software.

Some educators are beginning to speak out on the potential dangers of putting a child on the computer at too young an age.

"Parents are so intimidated. They think if they don't get their child a computer by the time he's two months old, he'll never get into Harvard," says Douglas Sloan, a professor of history and education at Columbia University Teachers College in New York.

Sloan believes that children who are exposed to the computer too early may be the real losers, because the narrow, logical way of thinking the computer teaches may stifle young children's imagination and hurt them academically in the long run.

Sloan, former editor of the Teachers College Record, devoted his entire farewell issue last summer to the criticisms of some educators and other experts about today's push toward computer-based education.

Throughout the volume, educators, writers and psychologists warn that the computer could undercut a child's imagination, interfere with learning, and force youngsters into an artificial, electronic world.

Those critics are in the minority, Sloan reports. Most American educators have jumped on the computer bandwagon without taking the time to examine carefully how the new technology can be used appropriately and what damage it could do.

"Children who learn to draw birds and flowers on the computer don't get any real sense of nature or of art," says Sloan. "It's an image kids don't even have to create. What happens to the imagination of a child who is always supplied with the image -- an image that is removed from reality?

"What could they possibly learn about drawing from pushing a button and having the computer draw a perfectly straight line on the screen? They don't find out how difficult it is to draw a straight line."

The criticisms raised by Sloan and other critics are valid but greatly overstated, says Kenneth Komoski, executive director of the Educational Products Information Exchange (EPIE), a nonprofit agency which evaluates educational software.

"For certain kids the computer could stifle creativity. For some youngsters who do not develop social ease, it could be isolating." But for the vast majority of students, Komoski says, the computer could be a tremendous educational boon if challenging, stimulating software is used.

Unfortunately, Komoski adds, "There is not much instructional protein" in most of the so-called educational software on the market today. About half of the programs are drill-and-practice software dressed up, he says, to look like arcade games. Kids talk their parents into buying it because it looks fun, but then they quickly get bored.

Good software is available, he reports, but there isn't much. He estimates that only about three or four of every 100 programs EPIE reviews is educationally challenging. One of the biggest problems parents face is sorting through the more than 7,000 programs on the market today to find the right ones for their children. Komoski would like to see schools help in that area.

"The schools are just wasting an enormous opportunity by not making parents aware of the computer's potential," he says.

"'It could be a major factor in improving education. With the use of home computers, TV viewing time goes down. Kids watch an average of 1,000 to 1,200 hours of TV a year -- more time than they spend in school. If we can erode that viewing time enough with good educational software, we could double the learning time of kids."