Given the decline in birth rates, which will produce a steep decline in the youth population by 1990, this paper examines the possible effects such a population shift will have on the achievement motivation of children. It is reasoned the increased adult/child ratio could result in either of two possibilities: the greater attention paid to the individual child might effect a greater sense of personal causation, leading to increased achievement motivation; or, the greater adult/child ratio could overwhelm the child, eventuating in a decreased sense of personal causation and/or motivation. Based on these two possibilities, this paper discusses two scenarios describing how it might be when "children of the 60's and 70's" hit the job market. In the first scenario, it is assumed that socialization in a small family increases achievement motivation. These highly motivated individuals will probably expect to accomplish great things in their employment. However, an analysis of the population trends indicates movement to upper level positions may be retarded because of a large older age group. Therefore, one might expect these children to be a frustrated generation. In the second scenario, it is assumed that socialization in a small family reduces achievement. In this case motivation to excell and do well at a job might be reduced. This latter situation might lead to a more peaceful coexistence between generations. (Author/JK)