Difference-education interventions teach people a contextual theory of difference: that social group difference comes from participating in and adapting to diverse sociocultural contexts. At two universities, we delivered difference-education interventions during the college transition and examined long-term academic and intergroup outcomes. Nearly 4 years later, first-generation students who received a difference-education intervention earned higher grades and were more likely to attain honors standing than those in the control condition. Based on an end-of-college survey with students at one of the two universities, both first-generation and continuing-generation students showed greater comfort with social group difference compared with students in the control condition. Our results demonstrate for the first time that teaching first-generation students a contextual theory of difference can lead to long-term academic benefits that persist until graduation. This work also provides new evidence that difference-education can improve comfort with social group difference.