Imagine two children heading off for their first day of school. Both are toting new school bags full of educational paraphernalia: pens, pencils, erasers , and paper.
But they are also carrying with them a parcel of language skills. And those skills may differ tremendously.
One child may have a vocabulary of 10,000 words; the other, as few as 4,000. One may have heard his favorite stories again and again, while the other may not have been read to as much. One may frequently play word games with parents, the other seldom does.
Will these differences determine their success at school?
They could, according to Dr. Catherine E. Snow of the Harvard Graduate School of Education. But they don't have to.
The language skills children acquire before starting school influence their academic work, but they do not guarantee success or lock them into failure, she says.
It has been suggested that children from minority or working-class families come to school with poorer language skills than their white, middle-class peers and that those deficiencies have led to academic failure.
According to Sarah Michaels, a research assistant at Harvard's Graduate School of Education, minority children bring to school different ways of telling stories. Her research shows that those differences influence a child's performance at school.
White children from middle-class homes tend to tell shorter, more concise stories that are organized chronologically. Teachers have no trouble understanding the point of their stories and tend to encourage them to expand on them.
On the other hand, teachers tend to be confused when black urban children tell their stories which are structured very differently.
''They tend to link a series of concrete episodes,'' Michaels said. ''It sounds often to (the teachers) that they are rambling on, that they aren't being organized.''
Teachers interrupt more often, trying to get children to conform, and the children get less positive reaction.
Seeing the differences and responding to them constructively is a very difficult task, Ms. Michaels says.
''The teachers are not stereotyping . . . they are not prejudiced,'' she says. ''They are responding to real differences in the use of language and in the way people structure narratives.''
But differences are not deficiencies, Dr. Snow says. And teachers who are aware of the differences can prevent these differences from holding children back.
Research shows that most children starting school have a good grasp of the language. They can both use and understand complex grammatical structures. But some children may not use complex structures as often, and the structures they do use may not conform to standard English.
The point is that the skill is there, Dr. Snow says. These children do not know less than their peers, nor are they linguistically handicapped.
The advantages of using the language better than other children can be subtle. Children who are skilled verbally will be better at important social skills. They may be more persuasive and more polite. They may be able to attract teachers to get more attention.
''A large vocabulary makes a kid look smart,'' Dr. Snow notes.
Children who are perceived as smart by both teachers and other students develop a better self-image and more self-confidence.
According to Dr. Snow, teachers need to be careful not to confuse a large vocabulary and courtesy with ability to learn. ''We all have a tendency to judge people by their most obvious social behavior, which is their language,'' she says. ''The way kids talk is not a measure of their innate capacity to learn. It is more a measure of what they have already learned, not what they can learn.''
But there are certain language skills that do make a difference when it is time for a child to learn to read and write, she adds.
The size of a child's vocabulary is a good indication of what reading group he or she will be put in, for example. The average vocabulary of a child starting school is about 6,000 words. But it is clear that the child with a larger vocabulary, ranging up to about 10,000 words, has an advantage.
A limited vocabulary is a problem that can be solved, she says, because children continue to learn new words readily. ''Every word a child learns is another word he has to use,'' Dr. Snow says. A small vocabulary doesn't become a serious setback in reading until the middle grades.
Another skill that seems to help a child become literate is the ability to play with words, to use them as objects. Children who play word games, such as finding words that begin with the same letter or giving definitions, are demonstrating this skill.
Most children are good at conversation. They can point, use their hands to show size, and make faces. And the person they are talking to can ask questions to fill in gaps. But it is more difficult to communicate with someone who isn't there, and that is exactly what is required when children learn to read and write.
There are ways that parents can help their children to develop good language skills easily, Dr. Snow says. And they can do it without actually sitting down and teaching particular skills.
''If a parent answers a kid's questions, a kid is creating enough opportunities to learn all of the words, all of the ideas that he needs,'' she observes, ''And the kid will go on asking questions.''
Parents can also do other things to develop language skills, such as watch television with their children, discuss and reread books, and play word games in the car, she says.
Parents should not feel guilty about leaving children in day-care centers, she said, because they are rich linguistic environments.
The important thing for everyone to remember, she said, is that the children who start school with poorer language skills are not doomed:
''They are going to be less effective - not dumber - first graders.''