them. People have different ways of treating a cheerful baby and a cranky one, an active baby and an apathetic one, or a healthy baby and a sick one. The "fit" between parents and child—the degree to which the parents feel comfortable with the child—affects parents' feelings. Energetic, active parents may become impatient with a slow-moving, docile child, although more easygoing parents might welcome a child with such a personality (A. Thomas & Chess, 1977). Language is a particularly striking area in which infants affect the world around them: when babies babble and coo, adults are more likely to talk to them, which then makes the baby "talk" more. This cycle of conversation helps chil­dren acquire the ability to use language—and to gain better control over their own lives.    

WE ARE PRACTICAL 

As two people who live in the real world, we examine research findings carefully to see how we or others can use them to solve practical problems. Basic research, the kind undertaken in the spirit of intellectual curiosity with no immediate practical goal, and applied research, which addresses an immediate problem, com­plement each other.

In fact, these two types of research often go together. Basic research into children's intelligence can reveal how a child of a particular age learns and thinks. Applied research can use that basic knowledge to develop age-appropri­ate education. If, for example, we wanted to know when children can grasp the concept of quantities and numbers, we might develop a program to test children of different ages on their ability to recognize and deal with number concepts. This would be basic research. If we then wanted to apply this research to teach number concepts in the classroom, we could design a program to try out differ­ent ways of doing this and see which way turned out to be most effective. This would be applied research.

Every chapter from Chapter 2 on includes a box titled "The Research World," which reports on new developments in either of these two kinds of research. Also, each of these chapters includes one or more boxes titled "The Everyday World." These boxes show how basic findings can be used to solve practical problems.

Meet Vicky and Jason
Real children are not abstractions. They are living, laughing, crawling, crying, shouting, shrieking, jumping, whining, skipping, reaching, thumb-sucking, nose-picking, diaper-wetting, tantrum-throwing, question-asking human be­ings. To help you see children more as they really are and to personalize the statements we make about the way children develop, we introduce two leading characters who will grow up as their story unfolds in this text. We follow these personages, whom we have named Vicky and Jason, from conception to the time we leave them (or they leave us) in adolescence. We also come to know Vicky's parents, Ellen and Charles, and Jason's parents, Julia and Jess, as we see them interacting with their children. And as we trace these families' adventures, we are reminded that whenever we talk about children, we talk not about ab­stract concepts in imaginary space, but about real children in a real world. Neither of these families, of course, exists in real life. And yet all these people exist in some way, since every anecdote in which they appear, and every fact that relates to them, is rooted in truth. Nothing about Vicky and Jason or their parents is made up. The stories about them are drawn from two sources. One source is the actual lives of real children, either our own children (four between the two authors) or children whom we have observed. The other source is reports of actual research; these give us a wider view of children, so that Vicky and Jason can represent the American "Everychild," developing normally.

NORMAL DEVELOPMENT
Normal development means proceeding through recognized developmental stages at a typical rate. Wide variations in normal development, however, allow for a great deal of individual difference. Throughout this book, we talk about average ages at which certain behaviors occur: the first smile, the first word, the first step. In all cases, these ages are only averages. No child is exactly average in every aspect of development. There is a wide normal spectrum of individual differences with respect to height and weight, walking and talking, understand­ing ideas, forming relationships, and so forth. Therefore, all the average ages we give should be regarded as flexible. Only when children deviate drastically from the norm is there cause for considering them either exceptionally advanced or retarded. The important point to remember is that all normal children go through the same general sequence of events, even though the timing varies greatly.

NO CHILD GROWS UP IN A VACUUM
Both Vicky and Jason are typical, normal children, who might be of any race, any religion, or any ethnic heritage. However, they share some characteristics that not all children possess. Both Vicky and Jason were wanted children; each is growing up in a home with two loving parents; each is healthy; each is free from financial want. Unfortunately, not all children grow up in such favorable cir­cumstances.

 

When we study the development of children growing up the way Vicky and Jason are, then, we cannot generalize our conclusions to children born to mal­nourished teenagers, or children who do not get enough to eat, are rarely spo ken

 to at any length, are neglected or abused, or receive a deficient education. These children are growing up in a world light-years away from the ideal. In this book we talk about what circumstances like these mean for children's develop­ment. We do not confine our discussions to either the ideal or the typical.

A Reminder: The Real World and Real Children
One item this book cannot provide is a living child. For that, you need to keep an eye on the real world and the children in it. Jason and Vicky can only begin to tug at you, to pull you from the laboratory into the real world. With their help, though, and with the new knowledge of children that you will gain as you proceed through your course in child development, you will look at every child you see with new eyes.

Observe the children about you—your sisters and brothers, nieces and nephews, daughters and sons. Observe the children you see in stores and res­taurants, on buses and airplanes, in playgrounds and front yards. Pause to listen to and to watch children as they confront and experience the wonder of ordinary life.

Look, too, at the child you once were yourself. Recall some of your own earlier experiences, which may help to illustrate the various concepts discussed in this book. Look at the world through the eyes of a child, and the wonder you see will become your own.

 to at any length, are neglected or abused, or receive a deficient education. These children are growing up in a world light-years away from the ideal. In this book we talk about what circumstances like these mean for children's develop­ment. We do not confine our discussions to either the ideal or the typical.

A Reminder: The Real World and Real Children
One item this book cannot provide is a living child. For that, you need to keep an eye on the real world and the children in it. Jason and Vicky can only begin to tug at you, to pull you from the laboratory into the real world. With their help, though, and with the new knowledge of children that you will gain as you proceed through your course in child development, you will look at every child you see with new eyes.

 to at any length, are neglected or abused, or receive a deficient education. These children are growing up in a world light-years away from the ideal. In this book we talk about what circumstances like these mean for children's develop­ment. We do not confine our discussions to either the ideal or the typical.

A Reminder: The Real World and Real Children
One item this book cannot provide is a living child. For that, you need to keep an eye on the real world and the children in it. Jason and Vicky can only begin to tug at you, to pull you from the laboratory into the real world. With their help, though, and with the new knowledge of children that you will gain as you proceed through your course in child development, you will look at every child you see with new eyes.

Observe the children about you—your sisters and brothers, nieces and nephews, daughters and sons. Observe the children you see in stores and res­taurants, on buses and airplanes, in playgrounds and front yards. Pause to listen to and to watch children as they confront and experience the wonder of ordinary life.

Look, too, at the child you once were yourself. Recall some of your own earlier experiences, which may help to illustrate the various concepts discussed in this book. Look at the world through the eyes of a child, and the wonder you see will become your own.

 to at any length, are neglected or abused, or receive a deficient education. These children are growing up in a world light-years away from the ideal. In this book we talk about what circumstances like these mean for children's develop­ment. We do not confine our discussions to either the ideal or the typical.

A Reminder: The Real World and Real Children
One item this book cannot provide is a living child. For that, you need to keep an eye on the real world and the children in it. Jason and Vicky can only begin to tug at you, to pull you from the laboratory into the real world. With their help, though, and with the new knowledge of children that you will gain as you proceed through your course in child development, you will look at every child you see with new eyes.

Observe the children about you—your sisters and brothers, nieces and nephews, daughters and sons. Observe the children you see in stores and res­taurants, on buses and airplanes, in playgrounds and front yards. Pause to listen to and to watch children as they confront and experience the wonder of ordinary life.

Look, too, at the child you once were yourself. Recall some of your own earlier experiences, which may help to illustrate the various concepts discussed in this book. Look at the world through the eyes of a child, and the wonder you see will become your own. 

 to at any length, are neglected or abused, or receive a deficient education. These children are growing up in a world light-years away from the ideal. In this book we talk about what circumstances like these mean for children's develop­ment. We do not confine our discussions to either the ideal or the typical.

A Reminder: The Real World and Real Children
One item this book cannot provide is a living child. For that, you need to keep an eye on the real world and the children in it. Jason and Vicky can only begin to tug at you, to pull you from the laboratory into the real world. With their help, though, and with the new knowledge of children that you will gain as you proceed through your course in child development, you will look at every child you see with new eyes.

Observe the children about you—your sisters and brothers, nieces and nephews, daughters and sons. Observe the children you see in stores and res­taurants, on buses and airplanes, in playgrounds and front yards. Pause to listen to and to watch children as they confront and experience the wonder of ordinary life.

Look, too, at the child you once were yourself. Recall some of your own earlier experiences, which may help to illustrate the various concepts discussed in this book. Look at the world through the eyes of a child, and the wonder you see will become your own.