Stern, D., Finkelstein, N., Stone, J. R., III, Latting, J., & Dornsife, C. (1994). Research on School-to-Work Programs in the United States (MDS-771). Berkeley: National Center for Research in Vocational Education, University of California.

New Findings from the NCRVE Longitudinal Study

New evidence on the effects of working while in high school comes from a longitudinal survey sponsored by the National Center for Research in Vocational Education (NCRVE). This survey is unique in having collected data on students' participation in co-op, school-based enterprise, and non-school-supervised work experience as well as extensive information about qualitative characteristics of students' jobs. The sample discussed here came from one suburban and one urban school district in the midwest and from one suburban and one rural district in the southeast. The districts were chosen because they all offered a fairly rigorous form of cooperative education. At each school, some students in the sample were participating in co-op, some in non-school-supervised jobs, some in school-based enterprises, and some were not working at all during senior year. Co-op students were deliberately oversampled to ensure a sufficient number for analysis. Data collection began in fall 1988 in two of the districts and in fall 1989 in the other two districts; the last wave of data collection took place in spring 1992. A complete description of the sample and survey procedures is given in Cagampang, Stern, Hopkins, Stone, McMillion, and McCarthy (1993).

Information from the fall and spring of senior year was used to classify students according to the nature of their current work experience. Some 40 percent of the sample were enrolled in co-op during the fall or spring but did not report any other kind of work experience, another 31% were participating only in non-school-supervised employment (NSWE), 1% were working only in school-based enterprise (SBE), 7% participated in both co-op and SBE during the year, 3% in NSWE and SBE, 2.5% in co-op and NSWE, and 0.7% did all three; another 14% reported no work of any kind in either fall or spring.

The fall and spring surveys asked students how many hours they worked during an average week. Students were asked to give the number of hours for weekdays and weekends separately, and the answers subsequently were added together. The mean for students who participated only in co-op was 24.5 hours, with a standard deviation (s.d.) of 8.7 hours. Students who enrolled in co-op and also participated in either NSWE or SBE worked an average of 26.0 hours (s.d. = 9.2). Those who did only NSWE reported an average of 21.9 hours (s.d. = 9.2). Evidently the co-op students worked longer hours. These differences are statistically significant, with F(2, 557) = 8.19, p = 0.0003. (Students who did not work are excluded from this analysis for obvious reasons; those who participated only in SBE are omitted because there were so few of them; and those who combined SBE and NSWE are not included because they were too few to analyze separately and adding them to the NSWE category would violate the non-school-supervised criterion that defines this category.)

Grade point averages (GPA) also varied among seniors with various kinds of work experience. GPA was computed from senior-year grades obtained from each student's official high school transcript. Top grades were in the NSWE-only group: mean = 2.66, s.d. = 0.68. Students who did not work at all had the next highest mean of 2.58 (s.d. = 0.77). Co-op students and those who combined co-op with either NSWE or SBE had the lowest means of 2.31 (s.d. = 0.57) and 2.27 (s.d. = 0.52), respectively. These differences are highly significant, with F(3, 505) = 13.2, p < 0.0001.

The relationship between GPA and hours worked per week is shown in Figure 2, the data for which is given in Table 3. Students were divided into groups of roughly similar size according to the number of hours they worked during senior year. The mean GPA for each group is marked with a dash ( - ), and the vertical line next to each dash shows the standard deviation of GPA within the group. The resulting picture shows GPA is highest among students who work a small number of hours each week and lowest for those who work the most. This is consistent with previous research described in the preceding section.

More important than high school grades is what happens to students after they leave high school. At the time of the last survey in spring 1992, 52% of these seniors from the graduating classes of 1989 and 1990 were combining work with some kind of further schooling, 25% were working but not in school, 18% were in school but not working, and 6% were neither working nor enrolled in school. The percentage in school was lower and the percentage working was higher than in nationally representative samples as reported in the first section. The reason is that the NCRVE survey deliberately over-sampled co-op students, who are more likely than other students to work and less likely to pursue postsecondary education.

Enrollment in postsecondary education as of 1992 was strongly related to high school grades as one would expect. The former high school seniors who were combining work with further schooling had the highest GPA as seniors: mean = 2.66, s.d. = 0.61. GPAs were very nearly as high among those who went on to postsecondary education but were not working in 1992: mean = 2.63, s.d. = 0.68. GPAs were substantially lower among those who were working but not in school or were neither working nor in school: means = 2.19 and 2.12 (s.d. = 0.58 and 0.53), respectively. The difference is highly significant, with F(3, 376) = 14.8, p < 0.0001.

Employment in 1992 and participation in postsecondary education were also related to type of work experience during senior year, as shown in Table 4. Former co-op students were more likely than other groups to be working but not in school. Former NSWE students were the most likely to be combining work with further schooling. Individuals who did not report working during senior year were more likely than others either to be in postsecondary school and not working or neither working nor in school. These differences are highly significant: Pearson chi-square = 83.5 with 9 degrees of freedom, p < 0.00001. This corroborates the finding from previous research summarized earlier, that high school co-op students are relatively unlikely to enroll in postsecondary education.

Those co-op students who did attend postsecondary school were relatively likely to enroll in vocational schools or two-year colleges and less likely to go to four-year colleges, as Table 5 shows. The group most likely to attend four-year college were former seniors whose only work experience during senior year was NSWE. The differences are highly significant: Pearson chi-square = 52.7 with 6 degrees of freedom, p < 0.00001.

Evidently, students who held co-op jobs during their senior year seem to have been more work-oriented and less oriented toward further schooling than their classmates who worked only in non-school-supervised jobs or who did not work at all. This is consistent with previous findings from the NCRVE baseline data, which compared co-op and NSWE students' perceptions of their jobs during senior year. The co-op students more frequently indicated at the time that their jobs were interesting, gave them opportunities to learn, made use of what they had learned in school, and were related to their desired careers (Stone et al., 1990).

Correspondingly, the follow-up data now reveals that former seniors who went to work but not to school in 1992 were more likely to have said that their senior-year jobs

• let them do the things they did best.
• taught them new skills that would be useful in their future work.
• influenced their career choice.
• made them want to quit school as soon as possible.
• gave them a chance to be helpful to others.
• were very challenging.

Chi-square tests showed the senior-year answers to each of these questions were significantly associated with whether individuals were in school, working, doing both, or doing neither in 1992.

These results are logically compatible with two different causal interpretations. Analysis of the NCRVE data, or of other data, has not yet provided a clear test of whether one or the other of these explanations accounts for more of the evidence. First, co-op students and others who find jobs that they like during senior year may have a greater probability, as a result, of going to work after high school and not continuing in postsecondary education. Alternatively, students who are already interested in going to work and not to postsecondary education may be more likely to enroll in co-op while they are in high school and also to make more positive statements about their high school jobs. Both explanations may contribute to the observed linkages between co-op participation, positive reports about senior-year jobs, and subsequent participation in work but not postsecondary education. However, these two interpretations have different implications for educational policy and practice. The first one implies that co-op and good jobs for students may divert them away from possibly beneficial participation in postsecondary education--may promote short-term well-being but reduce longer-term opportunities--and should therefore be limited or redesigned to avoid this harmful effect. The second interpretation assumes that students already know what is in their own best interest and implies that co-op and good jobs should be promoted to help students achieve their own purposes.

Further evidence from the NCRVE survey about the short-term monetary benefits from senior-year jobs can be found in the information on 1992 wages. Individuals who were working in 1992 were asked their hourly wage or, if they were paid by the week, their weekly earnings, which were then divided by hours worked per week in 1992. The sample mean was $6.19, s.d. = $1.98. Ordinary least-squares regression analysis was done with wage as the dependent variable. The predictors were as follow:

• whether the individual had participated in co-op during senior year
• extent to which (on a four-point scale) the senior-year job was said at the time to
  • provide a chance to help others
  • teach new skills that would be useful in the student's future work
  • help the student learn to communicate with others
• whether the individual was a member of a racial or ethnic minority group
• number of hours per week worked on the senior-year job
• whether the individual was male

For the regression as a whole, R-square is 0.153, F(7, 240) = 6.20, p < 0.001. Results for individual predictors are presented in Table 6. The only statistically significant coefficients are with the three reported characteristics of the senior-year job. Two of these coefficients are negative, indicating that positive attributes of the senior-year job are associated with lower wages later on. One possible explanation is that students who found senior-year jobs that enabled them to communicate with and be helpful to other people are more interested in non-monetary rewards from work than in obtaining the highest possible wages.

The third attribute of the senior-year job--whether it taught skills that would be useful in future work--is positively associated with 1992 wages. A straightforward explanation is that if students' jobs actually did teach useful skills, they were able to obtain relatively higher wages after leaving high school. This result is consistent with findings from the NLSY data (Stern & Nakata, 1989).

Although the regression coefficient on co-op participation does not quite meet customary standards of statistical significance, the bivariate association between co-op participation and 1992 wages does. The mean wage for former co-op participants was $6.40 (s.d. = $1.77) and $5.94 (s.d. = $2.19) for nonparticipants. This yields a t statistic of 2.04 with 308 degrees of freedom, p = 0.04.

However, on closer inspection, the wage advantage for former co-op participants is statistically significant only for individuals whose 1992 employer was the same as their employer during senior year. Among this subsample who did not change employers, the mean wage in 1992 was $6.71 (s.d. = $1.32) for the former co-op students and $6.09 (s.d. = $1.77) for the others. This gives a t statistic of 2.04 with 109 degrees of freedom, p = 0.04. In the subsample who did change employers, the mean wage in 1992 was $6.22 (s.d. = $1.96) among former co-op students and $5.85 (s.d. = $2.40) among the non- co-op group. This gives a t statistic of 1.18 with 197 degrees of freedom, which is not statistically significant. This replicates the finding of Stern and Stevens (1992). As stated above, it seems that co-op leads to higher wages if individuals stay with the same employers but not if they change. The benefits of co-op appear not to be portable.

In brief, these findings indicate that co-op participation yields a short-term advantage but also possibly a longer-term disadvantage. The short-term advantage is a gain in wages for co-op participants, compared to nonparticipants, as long as they stay with their co-op employer. The possible disadvantage is that co-op may steer students away from postsecondary education, and especially from four-year colleges, thus reducing their chances for later career mobility. These effects of co-op are not necessarily the result of the program structure itself. They probably reflect the fact that the co-op programs studied here, like most co-op programs in high schools, are tied to traditional vocational education programs that aim primarily to prepare students for immediate employment, not for further education.

Stern, D., Finkelstein, N., Stone, J. R., III, Latting, J., & Dornsife, C. (1994). Research on School-to-Work Programs in the United States (MDS-771). Berkeley: National Center for Research in Vocational Education, University of California.