Gender disparities in second-semester college physics: The incremental effects of a “smog of bias”

Our previous research [Kost et al., Phys. Rev. ST Phys. Educ. Res. 5, 010101 (2009)] examined gender differences in the first-semester, introductory physics class at the University of Colorado at Boulder. We found that: (1) there were gender differences in several aspects of the course, including conceptual survey performance, (2) these differences persisted despite the use of interactive engagement techniques, and (3) the post-test gender differences could largely be attributed to differences in males’ and females’ prior physics and math performance and their incoming attitudes and beliefs. In the current study, we continue to characterize gender differences in our physics courses by examining the second-semester, electricity and magnetism course. We analyze three factors: student retention from Physics 1 to Physics 2, student performance, and students’ attitudes and beliefs about physics, and find gender differences in all three of these areas. Specifically, females are less likely to stay in the physics major than males. Despite males and females performing about equally on the conceptual pretest, we find that females score about 6 percentage points lower than males on the conceptual post-test. In most semesters, females outperform males on homework and participation, and males outperform females on exams, resulting in course grades of males and females that are not significantly different. In terms of students’ attitudes and beliefs, we find that both males and females shift toward less expertlike beliefs over the course of Physics 2. Shifts are statistically equal for all categories except for the Personal Interest category, where females have more negative shifts than males. A large fraction of the conceptual post-test gender gap (up to 60%) can be accounted for by differences in males’ and females’ prior physics and math performance and their pre-Physics 2 attitudes and beliefs. Taken together, the results of this study suggest that it is an accumulation of small gender differences over time that may be responsible for the large differences that we observe in physics participation of males and females.

Figure 1

Tracking students through the introductory physics sequence. The chart above shows the numbers of males and females who took Physics 1 (between spring 2004 and spring 2008) and Physics 2 (between fall 2004 and spring 2009). The numbers in parentheses are the number of male and female physics majors (PHYS) at each step. Males and females are about fractionally equal at every step of the chart, except in the percentage of physics majors in Physics 2.

Figure 2

Pre- and post-test gender gaps $\left({⟨S⟩}_M-{⟨S⟩}_F\right)$ by semester. The data shown here includes all students who took the pre- and post-BEMA. These data represent seven different instructors and over 2500 students. The instructor is indicated along the $x$ axis. Instructors who taught more than once are labeled with a letter and a number. The error bars represent the standard errors of the mean.

Figure 3

FMCE and BEMA gender gaps $\left({⟨S⟩}_M-{⟨S⟩}_F\right)$ by semester. The gender gaps for each semester are shown above $\left(N=1487\right)$ for only those students who took both the FMCE (in the first-semester course) and the BEMA (in the second-semester course). The error bars represent the standard errors of the mean.

Figure 4

Average shifts (post–pre) for males and females in Physics 2 on each of the CLASS categories. Note that all shifts are negative or zero, meaning both male and female students shift toward less expertlike attitudes and beliefs about physics or remain the same. The asterisk $\left({}^{\ast }\right)$ indicates that the difference in shifts for males and females is significant $\left(p<0.05\right)$. Values in parentheses (on the right hand side) are female and male average pretest scores. The pretest scores of males and females are significantly different in all categories except sense-making.

Figure 5

Average BEMA post-test scores for females and males with matched FMCE post-test scores $\left(N=1117\right)$. The percentages above each bar represent the percentage of the females (or males) from the total in each bin. The error bars represent the standard error on the mean. The differences between males and females are not significant $\left(p>0.05\right)$ in all five of the bins.