Ryan Grywacz, a 10-year-old from Harleysville, Pa., wowed the coaches at a weeklong baseball clinic last summer. He could hit with power, possessed great speed, and had a blazing fastball. The staff spotted a future superstar. One coach saw a potential client.

That coach, Jack Aker, a former Major League Baseball player, tapped Ryan to work one-on-one with him in Princeton, N.J., about an hour’s drive from the boy’s home. The cost: about $90 an hour. The gain: Far superior instruction and individual attention than Ryan would ever get at his community Little League.

After four sessions, Ryan was yearning for more. He wanted to fine-tune his curve ball. Ryan’s father, Gary, was reluctant – not wanting to overwhelm his son – but finally consented. “I want Ryan to know that if he wants to improve at something, there are ways to make it happen,” Mr. Grywacz said. “There are people who can help and give you direction.”

Not all parents are so hesitant. Many mothers and fathers are craving private coaches for their children, hoping to get them up to snuff or give them the extra edge to make the A-team. For many children, a weekly private sports tutor is one more after-school activity in an already hectic schedule. But parents and the athletes themselves say the time is worth the effort and the cost.

To be sure, budding ballerinas, tennis stars, swimmers, and gymnasts have been training individually for generations. But a personal coach for children who participate in team oriented sports is a completely different ballgame, say physical education authorities. Advocates say these pros-for-hire are offering children a unique opportunity never before available. Yet critics claim these coaches are adding another stressor to an already high anxiety life. They worry that adult-supervised free time clobbers a child’s ability to develop social skills and creativity. Remember back yard ball games of yesteryear, when kids negotiated the rules and called all the shots? There was a point to the madness, say experts. Amidst the seeming chaos, young people were learning social skills and creativity. So are these pros-turned-teachers luxuries or killjoys?

“I don’t think all coaching is bad. I’ve seen kids go from clutzy to pretty decent players and they feel better about themselves,” said Dr. Alvin Rosenfeld, a child psychiatrist in New York City and co-author of “The Overscheduled Child” (St. Martin’s Press, 2000). What worries Dr. Rosenfeld is the vanishing time for children to be children. “Should we allow kids to construct fun in their own world, or should we as adults be the authors of their lives?” he said. “Children’s baseball used to be about social development. We have stolen childhood.”

No one keeps track of the number of clients receiving private coaching – coaches do not have to register and are not required to have a license – but those in the business say demand has skyrocketed, prompting an increasing number of former pros to join in. They hear from parents whose children are a bit clumsy and just want them to be good enough to participate in community sports, or at least attain a passable level for physical education classes. And of course, there are the overly zealous mothers and fathers hoping their child will one day be good enough for a college scholarship or gain an edge for admission to the Ivy League.

Coaches say their superior technical training not only boosts a child’s confidence on the playing field, but in all their daily activities. Indeed many personal trainers become a child’s confidante, encouraging sportsmanship and a true love of the game. And who better to model yourself after but a former major leaguer?

Greg Kenney, a trainer in New York City, helps children as young as 9 with soccer and baseball. “I think kids are overbooked. They’ve got academic pressures. I don’t think adding one thing to an already full plate is making the difference.” Mr. Kenney and many other coaches said they are not to blame for a child’s stress. If anything they minimize the pressure that often comes from overly eager parents.

Judith Young, vice president for programs of the American Alliance for Health, Physical Recreation and Dance, in Reston, Va., is somewhat skeptical of private coaching, but agrees that a good coach with the right child can have a very positive influence. “I think it depends on the child and the trainer and how this fits into the whole context of the child’s life,” she said. “There are trainers that can bring balance and perspective to the parents. In some cases they may be the voice of reason.”

Critics say individual coaching is the next step in hyper-parenting – mothers and fathers striving to mold perfect offspring. They yearn for the days when children ran outside with just a ball and a few friends. Despite whatever comforting words a parent may offer, hiring a coach is a clear signal that they are more concerned about their child’s athletic prowess than simply having fun with sports.

“There is a big craze that so-and-so has a personal trainer and we have to get one. I think the bottom line is that we as a society have our priorities backwards,” said Dr. Eric Small, chairperson of the American Academy of Pediatrics Committee on Sports Medicine. He is also the author of “Kids & Sports” (Newmarket Press, 2002).

Dr. Kyle Pruett, professor of child psychiatry at Yale University, agrees. “My concern,” said Dr. Pruett, “is that you are diluting the peer experience with one more skilled adult with whom to identify as a mentor and leader instead of your best buddy. It short circuits an opportunity for problem solving and leadership skills.”

There are no studies evaluating the effectiveness of coaching for 9- or 10-year-olds. Dr. Small suspects that playing ball with a friend or sibling would lead to the same incremental advances. Practice, regardless of the expert advice, will help a child improve.

Among the cacophony of opinions, there is one thing that everyone agrees on: Whether private coaching is a success depends on the personality of the youngster, the credentials of the instructor, and the attitude of the parents. Choosing the right coach is crucial, said Eric Heinzmann, director of the Youth Sport Research Council at Rutgers University. Though he does not condone the trend, he said that parents who are insistent about personal coaching should hire someone who understands young children, physically and emotionally. As any soccer parent knows, there are coaches who may have excelled in a sport, but they cannot relate to young children.

Parents should also be aware of clues that a child is feeling overextended. Many children will not complain, fearing they are disappointing eager parents. But they may begin to suffer from vague symptoms, such as sore throats, bellyaches, and extreme fatigue, that strike suddenly right before a coaching session or important game.

So what about Ryan? Is he feeling the heat? Not at all. Ryan said his parents care a great deal about his school grades, but not about baseball. Besides, he said, the sessions are “fun and they help me with pitching mechanics. I never feel like I’m under pressure. Only when I’m on the mound, bases are loaded and no outs.”

When it comes to private coaching, it seems the game has just begun. Only time will tell if these mini-athletes will burn out before puberty or develop into confident superstars.