Research paper accepted for presentation at the annual meeting of the American Educational Research Association, Montreal, Canada: April 2005

Transcription

1 The Relationship Between Interest in Physical Science/Engineering, Science Class Experiences, and Family Contexts: Variations by Gender and Race/Ethnicity Among Secondary Students Research paper accepted for presentation at the annual meeting of the American Educational Research Association, Montreal, Canada: April 2005 Shannon K. Gilmartin, California Institute of Technology Erika Li, California Institute of Technology Pamela Aschbacher, California Institute of Technology Cameron McPhee, Child Trends Please direct all correspondence related to this manuscript to: Shannon K. Gilmartin, Ph.D. Caltech Precollege Science Initiative California Institute of Technology 1200 East California Blvd., Mail Code 1-98 Pasadena, CA Phone: This study is supported by a grant from the NSF, REC The content reflects the ideas and opinions of the authors and not necessarily those of the funding agency.

2 2 Abstract Drawing from a sample of 1, th grade students across four school districts in Southern California, this study is designed to examine the net effects of family- and science class-related variables on students interests in a Physical Science and/or Engineering career, with particular attention to variations in these relationships by students gender and racial/ethnic background. Findings indicate that the role of family science orientation is contingent less on gender than on race/ethnicity, and that students perceptions of their science class experiences are not strongly related to their science career aspirations, regardless of gender and race/ethnicity. Implications for patterns of underrepresentation in the science and engineering pipeline are discussed.

3 3 Introduction The fact that African American students, Latino students, and female students are underrepresented in the later stages of the physical science and engineering pipeline has been a subject of much academic attention in recent decades, and the volume of work on variables that explain the disproportionate attrition of these and other underrepresented groups is impressive. Still, gender and racial/ethnic differences in rates of science and engineering workforce participation persist (e.g., National Science Board, 2004; National Science Foundation, Division of Science Resources Statistics, 2004), even with relative gains over the past several years and even after noted researchers have long identified several barriers to degree attainment and career development in the sciences among underrepresented populations. The barriers are complex, involving both psychological and structural factors often in place by secondary school that make it difficult for underrepresented racial/ethnic minority groups and women to succeed in physical science and engineering fields (U.S. Department of Education, National Center for Education Statistics, 2000). That the issue enters public, non-academic discourse intermittently in part explains the tenacity of many of these barriers without more conversation outside of federal agencies and academic institutions, substantive change in and outside of schools is less likely. However, there remain gaps in the academic literature as well, or limits to what is known about students achievement and sense of possibility in physical science and engineering fields. As one important example, differences in the precollege science experiences and perceptions by race/ethnicity are neither as widely nor as well understood as are those by gender (Catsambis, 1995; Greenfield, 1996; Weinburgh, 1995). Given the projected retirement rates of U.S. scientists and engineers, rising challenges to attracting and retaining foreign-born science talent,

4 4 and the increasing numbers of college-age racial/ethnic minority groups in the U.S. who (with the exception of Asian Americans) have historically entered the scientific workforce at a rate far below their share of the national population (National Science Board, 2004), this area of research is timely and critical. As such, this paper puts to use data collected as part of a four-year study of students science identities and begins to address differences in science attitudes by gender and ethnicity among a diverse group of 10 th grade students. Driving these analyses were three research questions shaped by previous literature on ethnicity, gender, and science, as well as earlier studies of classroom and family contexts that prove strongly influential of students science interests and career aspirations: (1) How do science class experiences and family science orientation relate to students interest in a Physical Science/Engineering career, net of other variables that are related to students interest? (2) How do science class experiences and family science orientation explain, or mediate, the effect of other variables on students interest in a Physical Science/Engineering career? Alternately, how is the relationship between students science class experiences, family science orientation, and interest in a Physical Science/Engineering career explained or mediated by other variables? (3) How does the role of family and science class experiences vary by racial/ethnic group and by gender? In this study, the science pipeline in secondary school is broadly defined as the constellation of curricular and extracurricular behaviors, attitudes, and choices that prepare students for undergraduate, graduate, and professional work in science and engineering; some students are

5 5 positioned in the pipeline, by concerted virtue of their coursework, interests, and perceptions as well as structural characteristics of their school and home environments, while other students are positioned outside of the pipeline and pursue other ends. The goal of the study is to map the contours of this pipeline in ways that expand on existing research, in effort to ascertain early factors that clarify the continued and disproportionate opting out of physical science and engineering by women and members of African American and Latino racial/ethnic groups. Students self-reported interest in a Physical Science/Engineering career was selected as the outcome of concern given that women, African Americans, and Latinos are generally more underrepresented in these science fields as compared to their White and Asian male peers and as compared to their participation in the social and/or biological, or life, sciences 1 (National Science Board, 2004). Background of the Study Pipeline Patterns by Gender and Ethnicity Through successive stages of the science and engineering (S&E) pipeline, the numbers and percent share of women and members of racial/ethnic minority groups decline, the exception being those from Asian American backgrounds who are over-represented in the S&E workforce (according to recent national data, Asian/Pacific Islanders constitute 11 percent of scientists and engineers, versus 4 percent of the total U.S. population) (National Science Board, 2004). Gaps have narrowed over time, but there is considerable variation by field. As of 1999, women comprised just 23 percent of physical scientists and 10 percent of engineers, though constitute almost half of the college-educated U.S. workforce and over half of the U.S population; African 1 Though American Indian/Alaska Native students also are underrepresented in the science and engineering pipeline, this study focuses on Latino and Black/African American students (in addition to White and Asian/Asian American students) given the very small number of students in the study s sample who were American Indian/Alaska Natives.

6 6 Americans comprised approximately three percent of physical scientists and engineers, versus seven percent of the college-educated U.S. workforce and 12 percent of the overall population; and Latinos comprised approximately three percent of physical scientists and engineers, versus four percent of the college-educated U.S. workforce and 13 percent of the overall population (National Science Board, 2004; National Science Foundation, Division of Science Resource Statistics, 2004). Differences in science attitudes and achievement by race/ethnicity and gender are notable long before workplace data are collected. African American students and Latino students perform more poorly on math and science achievement tests as compared to nonunderrepresented minority and White students as early as elementary school (National Science Board, 2004; U.S. Department of Education, National Center for Education Statistics, 2000). Some research suggests that barriers to science achievement among underrepresented racial/ethnic groups are both structural and psychological in nature, though women of all racial/ethnic groups may face more psychological challenges to science achievement than do men (U.S. Department of Education, National Center for Education Statistics, 2000). Among college students, rates of matriculation in S&E majors vary more by gender than by race/ethnicity, but persistence through these undergraduate programs might vary more by race/ethnicity than by gender. That is, women may be considerably less likely than men to enter S&E programs at time of college entry; however, those who do enroll in S&E programs seem complete these programs at a higher rate than do underrepresented racial/ethnic minority groups like Latinos and African Americans (National Science Board, 2004; U.S. Department of Education, National Center for Education Statistics, 2000). Degree attainment rates are telling: when looking at the total number of Physical Science and Engineering Bachelor s degrees

7 7 awarded in 2000, White students constituted 66 percent of the share, followed by Asian students (eleven percent), Latino students (seven percent) and African American students (six percent). Men comprised 75 percent of the total number of Physical Science and Engineering Bachelor s degrees conferred (National Science Board, 2004). The Role of the Family in the Pipeline Many studies of the gender gap in science and engineering participation have investigated the role of family socialization (e.g., Dick & Rallis, 1991; Eccles, 1993; Frome & Eccles, 1998; Grotevant & Cooper, 1988; Jodl, Michael, Malanchuk, Eccles, & Sameroff, 2001; Manis, Thomas, Sloat, & Davis, 1989; Palmer & Cochran, 1988; Tenenbaum & Leaper, 2003). For example, Tenenbaum and Leaper examined parental beliefs about their children s science interest and ability, and found that parents of daughters are more likely to believe that science is difficult for their child than are parents of sons. The authors also found support for their hypothesis that parents attributions of their children s science interest and ability would predict children s own science interests and self-efficacy, as was demonstrated on self-rated scales. These findings, in combination with findings from other studies (e.g., Frome & Eccles; Jodl et al.), suggest that parents hold and impart different academic and career expectations for their children depending on the child s gender, and that these expectations contribute to the early emergence of stereotypical gender differences in children s self- and task-perceptions. These stereotypical views may discourage girls from enrolling in higher-level math and science classes because they doubt their ability to succeed in them and/or they do not wish to enter what they perceive to be a largely male domain. Even young women who persist in the male-dominated pipeline during college and choose science, mathematics, or engineering majors might continue to receive stereotypical messages from their family about gender roles and the relative value of

8 8 science. In one study, male students more frequently perceived their parents as being more supportive of their education and career goals, while female students more frequently perceived their parents as supporting family-related goals, like getting married and having children. This was true of women who were enrolled in both non-science and science-related major fields (Manis et al., 1989). Though less extensive than the body of research on the conditional effects of family by gender, previous work also has explored the conditional effects of family by race/ethnicity. Some of these studies have identified parental support as a direct predictor of majoring in science during college, whereas the role of parental educational attainment and occupation seems to operate indirectly, influencing student decision-making through the encouragement of certain careers and provision of financial resources (U.S. Department of Education, National Center for Education Statistics, 2000). The issue of financial resources is an especially important factor in persistence among students from underrepresented racial/ethnic backgrounds who major in S&E fields. Compared with White and Asian American students, African American and Latino students are more likely to exit the science pipeline because of barriers like familial obligation and financial hardship (U.S. Department of Education, National Center for Education Statistics, 2000). In a study conducted by Seymour and Hewitt (1997), Latino, African American, and Native American college students in S&E fields reported working multiple jobs to meet financial obligations to both nuclear and extended family members while at the same time taking care of their own college tuition. Many of these students reported having difficulty in keeping up with their studies and ultimately opted to switch to less demanding majors. The Role of Classroom Perceptions and Experiences in the Pipeline

9 9 Prior research on the role of classroom experiences in students decisions to persist through the S&E pipeline partly attributes gender differences in science achievement and attitudes to different patterns of socialization in science classes (e.g., Jewett, 1996; Jones, Howe, & Rua, 2000; Jones & Wheatley, 1990; Lee, 1998). Compared to girls, boys tend to enjoy more of every type of classroom interaction with teachers, including direct questioning, praise, behavioral warnings, feedback, and teacher touch. Boys also receive less remediation for negative behaviors such as calling out answers without raising their hands. Other studies suggest that boys have a greater level of science activity both in and out of the classroom, and that they are more likely to use scientific equipment in class and to participate in extracurricular activities with tools and scientific instruments (Greenfield, 1996; Jones, Howe, & Rua, 2000). These experiences give boys greater exposure to solving scientific problems and may help to increase their confidence and achievement levels in science courses. Conversely, a lack of such experiences may lower girls confidence levels and make them feel as if they are less skilled in science than are boys, thus leading them to opt out of upper-level science classes. Additional research on science classrooms has focused on classroom climate and students perceptions of their science teachers. In a qualitative study of high school girls experiences in a Physics class, Carlone (2001) found that girls viewed their science teacher as an authority figure with access to rarefied scientific knowledge that existed separately from and/or was distal to their own interests. Girls agreed that their Physics teacher was entertaining and clear, but his presentation of the material only reinforced the sense that science was the result of an unattainable genius identity. With respect to classroom climate generally, Wyer (2003) observed that for Biology and Engineering majors, a positive assessment of classroom climate increased the odds of high degree aspirations in science for women but not for men. To

10 10 underscore the importance of climate to female students, Seymour and Hewitt (1997) argue that many female S&E majors who feel unsupported in their classes and dissatisfied with low expectations of faculty and peers may well switch out of these majors in favor of finding a friendlier campus environment. This speaks to the much-discussed issue of a chilly climate for women in S&E fields (Hall & Sandler, 1982). The body of research on racial/ethnic differences in science classroom experiences suggests that minority females, particularly African-American females, need early experiences with science outside of the classroom to increase motivation to continue taking science courses (Jones, Mullis, Raizen, Weiss, & Weston, 1992; Kahle & Lakes, 1983). Both Black and White girls report increased science class enjoyment when classes are more hands-on and inquiry-based (Greenfield, 1996). Other types of racial/ethnic differences in science class experiences can be observed at the school level. An analysis of the National Education Longitudinal Study of 1988 finds that schools with large minority populations have fewer financial resources available and fewer curricular and extracurricular programs, such as high ability, advanced placement, and college preparatory programs (U.S. Department of Education, National Center for Education Statistics, 2000). In further support, Seymour and Hewitt (1997) found that 25 percent of all non- White students who switched out of a science-related major claimed that inadequate high school preparation in basic subjects was a major contributor to their switching decision. These variations in course opportunity and school resources would seem to have a substantial impact on racial/ethnic minority students interests in pursuing science as a career. Models of Academic and Career Choice Turning to relevant theoretical models of academic behavior and career interest, Parsons and colleagues outlined a model of academic choice in which students select their courses based

11 11 on their interpretation of past events and accomplishments, their self-rated abilities, and their opinions about the difficulty and importance of various tasks. These variables are heavily influenced by socializing agents, such as parents and teachers, who play a strong role in the development of students self-concept, perceptions, expectancies, and values (Parsons, Adler, Goff, Meece & Midgley, 1983). From this academic behavior model, Dick and Rallis (1991) outlined a parallel model of career choice, which focuses on individual and contextual factors that shape students occupational goals. Their model suggests that career choice is dependent on students self-concept and career values as derived from students interpretation of past events, their perceived expectations of socializers, their aptitude level, and the broader socio-cultural milieu. The academic and career choice models were specifically designed to help explain gender differences in these choices; both models attribute gender differences to variations in students interpretive frameworks and messages from key socializing agents, which together ground students academic priorities and professional aspirations. The model for the present study is loosely based on that of Dick and Rallis (1991) and, secondarily, Parsons et al. (1983) given the critical role each assigns to socializing agents (or students perceptions of these agents) in addition to students interpretation of past experiences as indirect antecedents of career choice. However, for the purpose of this study, students perceptions of science-specific socializing agents and experiences (e.g., family members and science class) were placed at the end of the model, after a series of background characteristics, attitudes, and behaviors, in order to examine how family- and classroom-related variables relate to students Physical Science/Engineering career orientation net of correlates like science selfconcept and demographic factors like racial/ethnic background. That said, the analytic approach of the study (described below) allows for exploration of the extent to which these family and

12 12 classroom variables both directly and indirectly act on students career aspirations, as catalysts for key antecedents and key antecedents themselves. This angle draws from both social cognitive and ecological theoretical frameworks to explore the interaction of contexts like family and science class with background characteristics and micro-level student behaviors and views. The point is less to test models of academic and career choice than to use these models and the relevant literature as a guide for considering what may or may not be important to students career interests in the fields of Physical Science and Engineering, with particular attention to variations by gender and race/ethnicity. Methodology Instrumentation and Sample Data for these analyses were collected as part of a larger research project designed to explore the development of secondary students science identities over time, and how these patterns of development vary by students gender, racial/ethnic background, and socioeconomic background. Funded by the National Science Foundation and titled Is Science Me? (ISME), the study involves annual surveys of two cohorts of students (7 th grade and 10 th grade) followed by in-depth interviews with a stratified subset of survey respondents. Seven high schools and seven feeder middle schools across four diverse school districts in Southern California participated in the first year of the project. The first-year ISME survey was positioned as a baseline instrument against which many items would be post-tested in subsequent years. Survey items were developed in accordance with previous literature on factors that explain and differentiate students interest and achievement in science. Topics covered on the survey included perceptions of science and scientists; interest in science, science-related, and non-science-related college majors and careers; family and peer

13 13 relationships; perceptions of science class and teachers; science-related activities and behaviors in and outside of science class; views about ethnicity, gender, and self; and demographic characteristics. Successive versions of the survey were piloted with local students to maximize item comprehensibility. A national group of advisors consulted with item development. Among the 3, th grade students across all seven participating high schools, 34 percent (N=1,247) completed the ISME Year 1 questionnaire in Fall 2003 (according to a logistic regression analysis of nonresponse bias in permission slip returns, odds of return were higher among female students and Asian/Asian American students, and lower among Black/African American and Latino students, though odds of receiving parental permission were no higher among one group than among another). The sample for the analyses in this paper is limited to 1,125 survey respondents who reported that they were enrolled in a science class at the time of the survey, marked their sex on the survey, and marked their grade level on the survey (a total of seven students were excluded by virtue of not responding to the latter two items). Girls comprised 56 percent of this sample (N=632); together, Latino students and Black/African American students comprised almost 30 percent of the sample (Latino N=249, or 22 percent; Black/African American N=81, or seven percent). White students and Asian/Asian American students comprised over a little over two-fifths of the sample (White N=218, or 19 percent; Asian/Asian American N=266, or 24 percent). Table 1 lists the distribution of this sample by gender, all racial/ethnic categories, and socioeconomic background. Racial/ethnic categories were derived from students self-reported ethnic background on the ISME survey; students who were classified as Dual Ethnicity marked two of the major racial/ethnic groups (White, Black/African American, Latino, and

14 14 Asian/Asian American 2 ), and students who were classified as Other marked three or more of the major racial/ethnic groups, marked Other, marked a racial/ethnic category that did not fall under the major groups (e.g., American Indian/Alaska Native), or skipped the question (though beyond the scope of this paper, additional analyses will explore science identity development among students in both Dual and Other categories to learn how these groups are different from and similar to their peers). Students were assigned to Low, Medium, or High socioeconomic categories based on their responses to several survey items (number of computers at home, whether father attended college, whether mother attended college, and whether student lived with mother only) in addition to supplemental free/reduced lunch data provided by three of the four participating school districts (if students were classified as free/reduced lunch, they were automatically assigned to the Low SES category). As Table 1 makes clear, a far greater percentage of Latino students fell into the Low SES category as compared to other racial/ethnic groups in this sample, due to demographic characteristics of larger population from which the sample was drawn (Latino students were concentrated at predominantly lower-income participating schools). Therefore, findings among the Latino students in this study mostly speak to the experiences of Low SES Latinos, although the multivariate analyses in this paper control for SES, as described below. It is also important to note how much smaller the Black/African American student sample is compared to the White, Latino, and Asian/Asian American student samples. Black/African 2 Students were classified as Latino/a if they marked one or more of the following sub-groups: Mexican/Mexican American/Chicano; South American/Central American; Other Latino/Hispanic (Puerto Rican, etc.). Students were classified as Asian/Asian American if they marked one or more of the following sub-groups: Chinese/Chinese American; Filipino/Filipino American; Japanese/Japanese American; Korean/Korean American; Thai/Thai American; Pacific Islander/Samoan, Hawaiian, or Guamanian/Other Pacific Islander/Pacific Islander American; South Asian (Indian subcontinent)/south Asian American; Southeast Asian (Vietnamese, Cambodian, Laotian)/Southeast Asian American.

15 15 American students were less likely to return permission slips and were severely underrepresented at two of the seven participating high schools; efforts to boost the size of this sub-sample in Year 2 are underway. However, when breaking down the Year 1 analyses and results by students racial/ethnic background, findings among Black/African American students necessarily must be interpreted with caution. INSERT TABLE 1 HERE Research Methods and Variables In order to identify constructs underlying groups of survey items, principal components factor analyses were conducted using varimax rotation techniques on data collected from all 10 th grade students who responded to the ISME survey. A total of 24 factors with Cronbach s alpha values greater than.60 were derived from the factor analyses (to improve the psychometric properties of the ISME survey, most items in factors with lower alpha values were either modified for or deleted from the Year 2 follow-up instrument, findings forthcoming). Factor scores were computed by summing the items to comprise each factor; if items were scaled differently, they were first converted to z-scores and then summed. Following a set of descriptive analyses (frequencies, cross-tabulations, simple correlations), several of these factors and additional items from the survey were included in a series of ordinary least-square regression analyses designed to explore predictors of students interest in a Physical Science/Engineering career. Students scores on the dependent variable were computed by summing their responses to two items on the survey: how interested they were in having a job as a Physical Scientist, and how interested they were in having a job as an Engineer (these items were part of a longer list of science and science-related jobs, each of

16 16 which was measured on a three-point scale: 1= Not interested, 2= Somewhat interested, and 3= Very interested ). Missing responses were coded as zero to execute the additive statement. Regression analyses were run among the aggregate sample of students (N=1,125, which includes students across all racial/ethnic categories but excludes as noted earlier students who were not enrolled in a science class at the time of the survey, students who did not mark their sex, and students who did not mark their grade level) and then separately by sex (Girls, N=632; Boys, N=493) and by the four major racial/ethnic groups (White, N=218; Black/African American, N=81; Latino, N=249; and Asian/Asian American, N=266). Since the percent of missing values for any given independent variable was never greater than seven percent for any one racial/ethnic group, missing values on independent variables were replaced with the mean of that variable by racial/ethnic group (independent sample t-tests by sex and by race/ethnicity indicated that there were more statistically significant mean differences on independent variables by underrepresented minority/non-underrepresented minority than by sex, hence the decision to split the file by race/ethnicity and replace means accordingly). Using forward-stepwise techniques, 35 independent variables (listed in Table 2) were blocked according to a hypothesized model that places family- and science class-related variables at the end of the analyses, or in the final block, to assess the predictive role of these critical variables net of other student-level variables that could also explain students interest in a Physical Science/Engineering career. These other variables were blocked temporally, with earlieroccurring variables like students socioeconomic background and overall grade point average held constant first, followed by students science behaviors outside of class in Block 2 and their perceptions of science generally, career goals, and plans to take science courses in Block 3 (of course, the temporal placement of these variables is mostly inferred given that the data were

17 17 collected at one timepoint). Pursuant to addressing the research questions, the point of this blocking scheme is to determine 1) the net effect of the family and science class variables on students career interests, 2) the extent to which these variables mediate the effect of other groups of variables, like students demographic characteristics, 3) the extent to which the effects of these variables are mediated by other groups of variables, like students science behaviors outside of class and students perceptions of science, and 4) how these patterns vary by gender and race/ethnicity. To accomplish the first three objectives, changes in the beta coefficients for each family and science class variable were tracked over the course of each regression by looking at their Beta-in values, or the Beta coefficient for a given variable if it were to enter the regression equation at the very next step. This provides information as to how the effect of these variables might be explained by other blocks of variables with which they are highly correlated; tracing changes in Beta (and Beta-in) coefficients as other variables enter the regression equation to examine direct and indirect effects is similar to the goals of path analysis (Astin, 1993). Independent variables in Blocks 1, 2, and 3 were selected on the basis of how closely related they may be to students career interests above and beyond family and science class contexts; put differently, these control variables were included to minimize the likelihood that observed relationships between family contexts, science class contexts, and Interest in a Physical Science/Engineering career were not simply artifacts of more influential variables that had not been accounted for in the regression model. Looking at the independent variables of interest to these analyses more closely (or those in Block 4 see Table 2), Family science orientation is a three-item factor that measures students perceptions of family interest in and value of science (e.g., students are asked to agree or disagree with the statement [My family] thinks science is

18 18 interesting ), while Family member has a science-related job is a dichotomous variable that simply measures if the student has a family member (parent, sibling, etc.) who does sciencerelated work. Among the four science class-related variables, one is self-reported science grade at the time of the surveys, and another is how often the student feels bored in science class (measured on a four-point scale, from Never to Always ). Science class engagement is a three-item factor that measures students participation in their current science class (e.g., students are asked how often they Ask questions in class ), and Science class perceptions is a six-item factor that measures how students perceive their current science teacher and their own content knowledge of the class (e.g., students are asked to agree or disagree with the statement My teacher thinks I could be a good scientist one day ). INSERT TABLE 2 HERE Findings Descriptive Statistics Table 3 lists the frequency distributions for the two survey items that comprise the dependent variable, Interest in a Physical Science/Engineering Career. Gender differences are notable and compatible with previous literature: twenty percent of the boys in this sample were very interested in becoming a Physical Scientist, versus 10 percent of the girls, and 35 percent of boys were very interested in becoming an Engineer, versus just 8 percent of girls. By racial/ethnic group, interest in the Physical Sciences was highest among Asian/Asian American survey respondents, and lowest among Black/African American survey respondents. Interest in Engineering was more evenly distributed by race/ethnicity, albeit the patterns are comparable: Asian students reported higher levels of interest in Engineering relative to their peers, and Black

19 19 students reported lower levels of interest in Engineering relative to their peers. However, White students were the least likely to mark very interested in response to this item. INSERT TABLE 3 HERE Simple correlation coefficients between the dependent variable and each of the six family and science class variables are telling (see Table 4). Among students in the full sample, correlations for all variables are statistically significant (p<.01), the strongest relationship being that between Interest in a Physical Science/Engineering Career and Family science orientation (r=.31). Only one variable is negatively correlated students interest in Physical Science and Engineering: feeling bored in science class (r=-.18). Simple correlation coefficients for girls and boys are mostly similar, the exception being Science class engagement (r=.17, p<.01 for boys; r=.07, p<.05 for girls). This suggests that the frequency with which students ask questions in science class, seek help from their science teacher, and participate in class discussions is more consistently related to interest in a Physical Science or Engineering career for boys than for girls, among whom other factors may be at work [e.g., perhaps the correlation is smaller for girls because their participation in science class does not necessarily indicate science interest per se, but a desire to do well in school generally, along the lines of Carlone s (2001) work on high school girls in Physics class]. Interestingly, the correlation between science class grade and career interest is slightly stronger among girls than among boys, which raises several questions for further exploration: Are girls aspirations to become scientists more closely tied to their actual performance in science class than are boys aspirations? Do girls who feel that they don t have the grades more likely to drop out of the pipeline than are boys? Why might this be? (For example, do girls sense that they must meet

20 20 different and higher standards than do boys if they are to succeed in predominantly male science fields?) Differences in simple correlation coefficients by racial/ethnic group are more pronounced. Among Latino students only, the positive relationship between Family member has a science-related job and the dependent variable is statistically significant (r=.23, p<.01); likewise, the positive relationship between Family science orientation and students interest in Physical Science and Engineering is strongest among Latinos (r=.38, p<.01), though statistically significant for all groups (p<.01). Taken together, these simple r s suggest that family-related variables may be more closely related to Latino students science aspirations than to those of their non-latino peers, for whom family is important, but the nature of their influence is less consistent. Looking at the science class variables, the strongest correlate of the dependent variable for White students was Science class perceptions (i.e., students beliefs about their science teacher and their own content knowledge), whereas the strongest correlate for Black students was Science class engagement (i.e., students behaviors in science class). Correlations for all science class variables were generally higher among Latino and Asian sub-samples than among White and Black sub-samples, meaning that science career interest might be more weakly related to certain sets of classroom perceptions and experiences among latter two groups. Indeed, on the basis of these simple correlation coefficients alone, different patterns by race/ethnicity are clear. The following multivariate analyses examine these variations in greater depth. INSERT TABLE 4 HERE Results of the Regression Analyses: All Students Among all students in the sample, two of the six variables in Block 4 entered the regression equation: Family science orientation and Family member has a science-related

21 21 job, the former a stronger positive predictor of students interest in a Physical Science/Engineering career than the latter (see Table 5). These findings indicate that perceived family science support and interest play into students science career aspirations above and beyond other and related affective and behavioral measures, such as students science hobbies and views. Notably, Beta coefficients for student background characteristics in the equation changed only slightly with the entry of both family variables, meaning that these variables did not mediate the effect of measures like Overall grade point average despite strong simple correlations (e.g., the simple correlation coefficient between Family science orientation and Overall grade point average was.27, p<.01). This is because variables like GPA had already lost significance with entry of related measures, including View: I think I could be a good scientist one day (i.e., the positive relationship between good grades and science career aspirations is partly attributable to positive science self-concepts among high-achieving students). All four science class measures lost significance before they were tested in Block 4. By looking at changes in the Beta-in coefficients of these variables (see research methods above), Current grade in science class lost significance with the entry of General science-related hobbies (i.e., the relationship between strong grades in science class and interest in a Physical Science/Engineering career can be partly explained by the fact that students with strong grades tend to be those who are involved in many science activities, itself an important factor in students level of science career interest). The remaining three measures lost significance with the entry of View: I think I could be a good scientist one day, meaning that students who are rarely bored in their science class, participate in science class discussions, and have positive perceptions of their science class also have positive science self-concepts, and a positive science

22 22 self-concept is by far the strongest predictor of interest in the fields of Physical Science and Engineering (in quotes because the causal order of these two variables is so ambiguous). Turning to other independent variables that were statistically significant by the last step of the regression, boys were more likely than were girls to express interest in a Physical Science/Engineering career, as were Asian students as compared to students from other racial/ethnic groups. Students who participated in many physical science-related hobbies (like using tools to build things ) and students who felt that earning a lot of money was an important reason for choosing a career also tended to be those students who expressed interest in a Physical Science/Engineering career. The more semesters of science that a student planned to take, the more likely s/he was to be interested in these fields. And as mentioned, agreement with the statement I think I could be a good scientist one day was strongly related to the dependent variable. Statistically nonsignificant predictors by the final step (p.05) included students overall grade point average, General science-related hobbies, and View: I think science is interesting. INSERT TABLE 5 HERE Results of the Regression Analyses by Gender Table 6 summarizes the results of the regression analyses that were conducted separately for boys and girls. Each model explained an equal amount of total variance in the dependent variable (R-square for boys=.22; R-square for girls=.23). For both boys and girls, moreover, Family science orientation entered the regression equation at the final step, suggesting that family members who value, advocate, and are interested in science-related topics make a difference to girls and boys science career aspirations, even after controlling for other measures that could explain this relationship and variation in the dependent measure (e.g., students

23 23 participation in science-related activities). Beta coefficients for other variables in the model did not change considerably with the entry of Family science orientation, though some changes are notable: in both models, the Beta coefficient for View: I think I could be a good scientist one day dropped with the entry of Family science orientation, meaning that the relationship between a positive science self-concept and family members who encourage their children s interest in science is true of girls and boys, as is the link between these two variables and interest in Physical Science/Engineering careers. The belief that People of my ethnic background are well represented in science in this country entered the model for girls only, but was reduced to statistical nonsignificance (p.05) with the entry of Family science orientation, suggesting that 1) girls science career aspirations may be more sensitive to perceptions of racial/ethnic representation than boys aspirations are (i.e., boys express interest in these careers regardless of the degree to which they feel that their ethnicity is represented in the scientific workforce) and 2) girls who believe that people who share their ethnic background are well represented in the sciences tend to have family members who are interested in science, itself a critical component in the development of students science identities. It seems probable that girls have a more positive perception of ethnic representation in the sciences (and hence, their chances of becoming a Physical Scientist or Engineer) when close ethnic role models and socializing agents like family members identify with and/or care about science. The positive and statistically significant simple correlation between the dependent variable and Family member has a science-related job was explained over the course of each regression, as this variable gradually lost significance with the entry of related measures like General science-related hobbies for girls (i.e., female students with family members who work in science-related fields were more likely to have many science-related hobbies, which is an

24 24 important indicator of Interest in a Physical Science/Engineering Career). As with the analysis of the aggregate sample, all science class variables lost statistical significance before Block 4; in other words, the relationship between class perceptions, grades, and behaviors and interest in Physical Science and Engineering was explained by measures like science views (e.g., I think I could be a good scientist one day ) and overall grade point average (for Current grade in science class i.e., students who report strong grades in science tend to be high-achieving students generally, and high-achieving students are more likely to be interested in a Physical Science/Engineering career; the relationship between grade point average and career interest remained positive and statistically significant by the final step of the equation for girls only, which corroborates an earlier point that achievement may be more important to girls science aspirations than to boys aspirations). Among other variables that entered each equation, being Asian was a positive predictor of interest for boys only, while being White and being Black were negative predictors of interest for girls only, though Black/African American girls lower levels of interest were explained by their tendency to disagree with statements like I think I could be a good scientist one day and their lower likelihood of having many Physical Science- and Engineering-related hobbies (why the Beta coefficient for being White among girls remained statistically significant and negative through the final step of the regression is unclear, although indicates this model does not include all factors that are important to the development of science career interests, especially among some groups of students). Additional variables that entered the regression equations are listed in Table 6. INSERT TABLE 6 HERE Results of the Regression Analyses by Race/Ethnicity

25 25 Table 7 summarizes the findings from the regression analyses run separately by the four major racial/ethnic groups. Each model explained roughly 25 to 40 percent of the variance in the dependent measure. Beginning with the family variables, Family science orientation entered the equations for Latino/a and Asian/Asian American students only, failing to explain any additional variance for White and Black/African American students above and beyond other variables in the model. As suggested earlier, the importance of family science support to students science career aspirations may be especially true of Latino students and, as these results indicate, their Asian peers; for White and Black students, by contrast, the role of family science support was entirely indirect, playing out through variables like science hobbies and science views. The mediatory role of Family science orientation with respect to student background characteristics was negligible for Latino and Asian students the negative effect of being female (for both groups) and the positive albeit statistically nonsignificant effect of grade point average (for Asian students, at the final step of the equation) held even after Family science orientation was controlled. Having a family member with a science-related job did not enter the regression equation for any racial/ethnic group; as Table 4 indicates, this measure was significantly correlated with Interest in a Physical Science/Engineering Career among Latino students only, a simple correlation that was explained over the course of this regression analysis with the entry of science views (e.g., the positive relationship between family members who conduct sciencerelated work and Latino students interest in becoming a Physical Scientist or Engineer is mostly due to the fact that these students tend to have positive science self-concepts). And with the exception of Science class engagement in the analysis of Physical Science/Engineering career interest among Black students, not one of the science class variables explained additional

26 26 variance in the dependent measure after related variables were held constant; indeed, for some racial/ethnic groups, many of these science class variables were not significantly correlated with Interest in a Physical Science/Engineering Career to begin with (see Table 4). That Science class engagement was a positive predictor of the dependent variable for Black students above and beyond other variables is a suggestive finding (why for Black students alone does participation in science class tie so closely to their science career interests?), but should be interpreted cautiously given the relatively small sample size. Other findings of note in these analyses by racial/ethnic group: regardless of students racial/ethnic background, boys were more likely than were girls to express interest in becoming a Physical Scientist or Engineer, though for some groups, this gender difference was reduced with entry of variables like science hobbies (e.g., 10 th grade male students reported higher levels of involvement in science-related activities than did 10 th grade female students, which explained some of the gender differences in career interest among, in particular, Latino and Black student samples). A positive science self-concept (agreement with the statement I think I could be a good scientist one day ) was the strongest predictor of the dependent variable for Latino, White, and Asian students, but did not enter the regression equation for Black students. Views about ethnicity in relation to science were significant for Black and Asian students: Black students were more likely to express interest in a science career when they believed that people who shared their ethnic background were well-represented in the sciences; and Asian students were less likely to be interested in a Physical Science/Engineering career when they agreed that people who shared their ethnic background had trouble getting science jobs (the finding that Latino students were more likely to express science career interests when they agreed that people of their same gender have trouble getting science jobs was not only statistically nonsignificant by