Practical Implications

If the theoretical model in present study was considered under the background of Lewin‘s Field Theory and Bronfenbrenner‘s Ecological Systems Theory, great practical implications were to be offered for people and institutions of all levels: parents, teachers, school administrators, extended family, mentors, work supervisors, legislators, and government etc. For instance, after the implementation of China‘s One-Child Policy, women have more chance to enter into full employment. Hence the so-called equality between women and men in employment world brought more work to Chinese women besides the housework at home and an increasing divorce rate to Chinese household. Due to mother‘s full employment, their only-children do not have the constant mutual interaction with their mothers, which is necessary for development of children. According to the ecological theory, if the relationships in the immediate microsystem break down, the child will not have the tools to explore other parts of his environment (Bronfenbrenner, 1979). And apparently, parents could also do something in exosystem to help their children. For example, the mother could try to find a job requiring less work hours on weekdays and find more time to increase their

own interactions with their children to create more opportunities for their children to interact with others etc. within a microsystem, parents at least could, through their direct (e.g., appropriate parenting style) and indirect (e.g. providing a general family environment with high family cohesion) interpersonal behavior, exert their impact; they could also encourage their only-children to increase interactions with their peers and teachers to improve the dyad quality, say, a primary dyad; and meanwhile increase their own interpersonal behaviors with teachers to get more information about other systems in order to decide in time what to do to help their children. Finally, in a macrosystem, parents could do something for their children‘s rights to express their opinions to some institutions. For example, although it has been realized that there is necessity for the continuity of China‘s One-Child Policy and there are less social relations of the family due to the impact of this policy, the only-children need peers, other extended family members and even other adults. As parents, they could ask the government to make it a law that each community shall establish some play grounds for children and create more microsystems for children to interact with their peers, make use of the characteristics of Chinese culture (relational and collective culture) to develop relations with other families with similar aged children and improve social contact with extended family members and other adults such as grandparents and their friends.

Great implications for the practice of teaching are offered as well. Knowing about the breakdown occurring within children‘s homes, it is possible for our educational system to do some mending work to some degree. As the result in present study showed, teachers, especially favourite teacher interpersonal behavior had great impact on mastery goal, positive self-esteem, and social competence as well. And, of course, teachers and schools could try to create some ways or occasions to help increase the interactions or communications between students and their parents.

public policies and new laws. For example, to ease the social burdens brought by China‘s One-Child Policy and the accelerating aging process of the population, Chinese government could have taken some measures earlier in health insurance systems.

Not only people and institutions at all levels should create more interpersonal structures for these only-children, but also they should attend to the quality of these interactions. As Bronfenbrenner (1979) noticed that dyads (or other n＋2 system) had different qualities, such as observational dyads, joint activity dyads and primary dyads and the quality of dyads could be improved through improving reciprocity and affective relations, and controlling balance of power (p. 56-59). In present study, for example, peer group acceptance and best friendship quality both as peer relations had different importance to different outcomes and they also interact differently with other systems.

Since different systems or interactions between different systems might have different effects on different outcomes, to solve different behavior or development problems, there should be different concentrations on systems. For example, in present study, father parenting style and best friendship quality had great impact on positive self-esteem, but no impact on negative self-esteem. Therefore, when there is problem with an only child on negative self-esteem, solutions should be found in systems like peer group acceptance, favourite teacher cooperative behavior and favourite teacher opposition behavior

More attention should be given to biopsychological environment. Since there existed interactions between the learning environments and between student chronic self-concept levels and the learning environment, this emphasized the great importance of increasing interactions between the learning environments by interpersonal behavior, exchange and sharing of information between Microsystems. And in learning environments, adjustments in interpersonal behaviors are necessary on base of student different chronic self-concept levels. That is, to different students, same interpersonal behavior might function differently.

The present study also implied the great impact of a macrosystem, that is, the Chinese culture. Although the direct and interaction effects of Chinese culture were not tested through data analyses, chronic self-concept levels of these Chinese only-children expressed the print of Chinese culture, with relational level and collective level loaded most but individual level loaded least. Probably due to this cultural impact in that they could turn to others easily, on anxious solitary behavior, Chinese only-children did not record high although they have fewer extended family relatives and have no siblings or cousins in the family or extended family. This implied again that for the development of Chinese only- children, turning to macrosystem for help really functioned as well. On the other hand, other factors in macrosystem might disturb the development of children. To some degree, China‘s One-Child Policy is an example. As mentioned before, chronic self-concept of Chinese only- children still concentrated on relational and collective levels of self-concept, but how come they could have an individual-level-like career orientation. Probably this phenomenon is a reflection of the helpless souls because on the one hand, together with this public policy, the government has not taken complementary measures in time; on the other hand, Chinese only- children felt helpless and had no other choice, but to take the heavy social burdens on them alone.

In short, the present research has great implications to parents, teachers, educational researchers, as well as to policy-makers and practitioners in terms of finding a more integrated theoretical model, improving student outcomes, and creating better series of systems ranging from microsystem, mesosystem, exosystem, macrosystem and chronosystem.