Tutors for tots? More families like the idea.

Natalie Bloomster spends two afternoons every week with her tutor, reviewing the basics of reading, writing, and arithmetic.

There's nothing very unusual about this arrangement - except for the fact that Natalie is only 5 and not yet enrolled in school.

She was matched with her tutor through Junior Kumon, a tutoring program for preschoolers, designed to promote learning in children once considered too young for academics.

Natalie begged to be enrolled in the program, says her mother, Karen.

"Our son, Nathan, started coming to Kumon because he was struggling in school and Natalie would come to the center with me to wait for him," explains Ms. Bloomster, a mother of two in Tigard, Ore. "After a while she started begging me to sign her up so we wrapped up the [enrollment] packet and gave it to her for Christmas."

Natalie can now read several simple words, count to 200, and identify the sounds associated with each letter of the alphabet.

A growing number of parents across the country are enrolling preschoolers in tutoring programs, hoping that early education will prepare them for school and help them to become successful students.

"Children can achieve greater success in school if they get an early start in an academic program," says Dean Bradley, the vice president of instruction for Kumon North America in New Jersey. "The program] is interactive and fun for the children and helps them get a head start."

But some critics argue that structured academic programs for preschoolers are doing more harm than good.

"There is no research that shows that early academic programs have a lasting positive impact on children," says David Elkind, professor of child development at Tufts University in Medford, Mass. "In fact studies show that the high pressure of early academic programs can result in children with higher anxiety levels and lower self-esteem who are not doing any better academically."

Tutoring programs aimed at preschoolers exploit parental anxieties and undermine parental confidence, says Dr. Elkind.

"Parents are being told that they need an expert to do everything, including teaching their little ones how to read and write before they are ready," he says. "Parents should teach their children by responding to their questions and initiatives; they should not be pressuring them to learn."

But despite questions like those raised by Elkind, such programs are gaining in popularity. Kumon North America does not track enrollment based on age but Mr. Bradley says the number of students enrolled in the 2-1/2- year-old Junior program is growing steadily.

"Since the program started, we have seen a huge increase in the number of children coming in as preschoolers," Bradley says. "It is the fastest growing segment of our student population."

Some educators argue that early academics can be fun for children.

"A lot of people think that we are forcing preschool kids to learn, but it's not like that," says Marga Bailey, director of Junior Kumon in Tigard. "Kids at that age are sponges; they want to learn."

Parents struggle to find the right balance between providing a consistent learning environment and putting too much pressure on their children, says Ms. Bailey. "Some parents make learning too challenging or expect their kids to learn things too quickly. We try to lighten that pressure and provide the consistency that children need to learn."

Susi Scholl is confident that enrolling her five-year-old daughter, Erica Mendel, in a tutoring program at the Skibby Learning Center in Newport Beach, Calif., has made a huge difference in her academic preparedness.

"She is a very bright child but she took a huge leap forward with [tutoring]," says Ms. Scholl. "Within a month she was adding and subtracting three-digit numbers and now she is learning fractions."

Scholl, who pays $45 for each 30-minute tutoring session, says she believes tutoring is an investment: Not only is Erica thriving academically, Scholl hopes the extra instruction will give her daughter an edge when she applies to private school.

"Kids need to be on the cutting edge academically to get into a good private school," Scholl says. "Erica was craving the extra enrichment; her self-esteem has soared because of everything she has learned."

Critics are too quick to dismiss the benefits of preschool tutoring programs, especially in a changing academic climate in which children are expected to perform earlier,says Jo Skibby, founder of the Skibby Learning Center.

"Kindergarten today looks like first or second grade did 10 years ago," she says. "Preschool is developmental but tutoring is academic; preschool programs are not exposing children to all of the concepts we expose them to here."

Meanwhile, Natalie's mom says she remains confident that both Natalie and her brother have benefitted from being tutored at an early age.

"Both kids have learned so much and we have seen a huge improvement in their confidence and their skills," she says.