Based on eighth-grade writing assessment data from the 1998 (N = 20,586) and 2007 (N = 139,900) National Assessment of Educational Progress (NAEP), this study examines the relationships among students' writing attitudes, learning-related behaviors, and gender in relation to writing performance. Overall, the effects of attitudes were slightly larger than the effects of learning behaviors on writing performance, and gender differences were more prominent in attitudes than learning behaviors related to writing. Perhaps the most surprising finding from the 2007 NAEP data was that females with the most negative attitudes toward writing outperformed males with the most positive attitudes (i.e., writing scores based on two measures of attitudes: females, 157 and 161; males, 151 and 149). Overall, a similar pattern was observed with learning behaviors and gender differences in writing scores. Furthermore, medium effect sizes of gender difference in writing scores (females scoring substantially higher than males) were present even though the students reported to be at the same level in terms of writing attitudes and learning behaviors. The present study demonstrates that gender disparity in students' writing performance is persistent and strong; it cannot be explained by gender differences in attitudes or behavior alone or in attitudes and behavior combined. (Contains 9 tables, 1 figure, and 1 note.)