Why do the rich get richer? A structural equation model to test how spatial skills affect learning with representations

ABSTRACT Spatial skills predict students' success in STEM domains. This paper aims to better understand the difficulties of students with low spatial skills in using interactive graphical representations. I present a mediation analysis with test and log data from 117 students who worked with an intelligent tutoring system for chemistry. The analysis is based on (1) a knowledge component model that describes knowledge students acquire as they solve problems with graphical representations, (2) a search for features that describe students' interactions with the representations and that are predictive of students' learning gains, and (3) a structural equation model that tests whether these features statistically mediate the effect of spatial skills on students' learning gains. Results show that only students' ability to plan representations before they construct them mediates the effect of spatial skills on learning gains. This finding suggests that these students may need more support before they construct representations