Q. Our 2-year-old daughter, an only child in a neighborhood with few children, will enter a one-morning-a-week nursery school this fall, so she will have more social exposure. In observing the program, I was concerned about the mid-morning snack: a sugary fruit drink and cookies.

My husband is a dentist and I am an educator, and we find this practice inconsistent with our training, our values and our practices at home. Little children need wholesome foods for their growing bodies and with the problems of obesity, diabetes and tooth decay, I feel little justification for such a "menu."

Moreover, the children lose a valuable learning experience by not being exposed to more nutritious foods such as cider, juices, pineapple, melons, cheeses, seeds, etc. We can provide these foods for our daughter to take to school, as her teacher suggested, but are concerned about singling her out as different. Or--since cost is an issue--we could pay for the difference so all the children could have more nutritious snacks. But because the food comes from a central distribution center in the school, this would be a logistical problem.

How can we maintain standards of health for our daughter without sacrificing her social experience? We realize compromises are necessary for special celebrations, but it's hard to condone a routine practice that we think has no educational and nutritional merit.

A. Of all the discussions that crowd the nursery-school agenda, surely none are more persistent or more fractious than the Great Snack Debate.

It's hard to believe that a 10-minute snack could bring out such emotional feelings, but it does. This simple menu can drag meetings to midnight (although if it didn't something else probably would) and divide good friends. No parent takes school as seriously as the nursery-school parent, not necessarily because the school is so important but because the child is. It's a matter of letting go, which is always tough the first time and even tougher to admit to ourselves. Instead we make food the battle cry.

And with good reason. Good food is immensely important to the body as well as to behavior. Junk food often sets off disagreeable reactions, whether because of the sugar, the chemicals, the lack of nutrition or the appetite it ruins. Eaten regularly, it's sure to cause some kind of trouble, but many parents would still rather pay dentists, doctors and therapists than change the diet that might be causing it.

This still doesn't, however, give you leave to change the snack at nursery school. Unless your child is allergic to one of the ingredients, one snack once a week is not going to lead her down the road to perdition. To give her special foods would make her feel different, which would hurt the social experience and make the school snack even more appealing. It also would teach her that food can be a weapon--a poor lesson to give a child--and it would make her resentful.

To pay the extra cost of a nutritious snack for everyone would annoy the other parents and the teacher and could make the social experience pretty unpleasant for you. And it probably would annoy the children. Most 2-year-olds wouldn't swap their cookies for a handful of seeds.

Nor do you demand changes as soon as you enroll your child, any more than you would invite yourself into a neighbor's house and then criticize the furniture. A head-on collision is not the best way to win others to your point of view.

You can, however, have your husband go to the fall meeting, and as a dentist as well as a father, he could offer to send "natural toothbrushes" to the school each week: an apple quarter (covered with lemon juice to keep its color) or a piece of carrot or celery for the children to chew after their snack and thus remove much of the sugar from their teeth.

This will give parents the chance to ask an expert about the value of cookies and a "juice" drink, rather than have the answers shoved at them.

When you let your child go, you have to trust her as well as others. They'll all make mistakes, but it's as important to teach your child to act with sensitivity as it is to eat sensibly. Both are lessons best learned at home.

Q: Our son is 2 1/2 years old and not yet toilet trained, even though his two older brothers were fully trained by this age.

For a few months we tried to encourage him and then we teased him about wearing diapers. Neither worked. Now we punish him for "accidents" and lock him in the bathroom for about a half-hour.

He has started to use the cat's box. He also has been writing on the bedroom walls with crayons while my wife and I are at work.

Is this behavior normal?

A: His behavior is normal, but yours needs a little retraining.

Your little boy is telling you in the best way he can that he's not ready to be trained yet; that he's an individual, with an individual time-clock; that he's in charge of his own body and that he's mad. And you'd be mad, too, if you were mocked or locked in a room.

It's annoying to change and wash diapers, but it isn't a big deal. Let the child be. He'll train himself when he's ready and you stop fussing about it.

Did you ever know anybody who wore diapers to college?

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