Participation in work activities by high school students has been increasing over the past 25 years to the point where today at least one-third of all high school students hold part-time jobs in any given week. Student participation in work varies by geographic region and type of community, with older, white, middle-class, male vocational students from the Northeast and north central region being the most likely to be employed. Although students may be found working in all industries, they tend to be concentrated in wholesale/retail trade, service, and agriculture/forestry/fishing. Male students tend to work more hours than female students, and white students work more than do minority students. Weekly income averages $60-$70, with males earning more on average than females. The effect of working on grades is unclear. There seems to be a curvilinear relationship between hours worked and grades, with 20 hours being the point where a negative effect emerges. Working appears to have little effect on educational plans but is positively associated with employment and income after high school completion, at least in the short range. Working during high school appears to promote desirable work habits. In general, relationships with parents and siblings are not affected by working. Findings regarding the effect of working on delinquent behavior are inconclusive and contradictory. There is a general need for improved and more comprehensive data related to youth and work; in addition, a common set of measures regarding working, reasons for working, the multiple dimensions of student work experiences, and the multiple attitudinal and behavioral outcomes of working is needed. (An annotated list of major data sources on youth and work is appended. Commentaries by Sue E. Berryman and Hayes Mizell are included.) (MN)