Sexual assault is a pervasive problem that has devastating consequences for college students. California's legislation stipulates that public colleges and universities must define sexual misconduct and sexual consent as well as provide ongoing sexual assault prevention education on campus. Despite these efforts, little is known about how well students understand consent or whether their knowledge differs by gender identity and sexual orientation. To address this gap, we collected data from 291 students attending a public university in Northern California and found that most (presumably well-informed) students had only cursory understandings of consent. We argue that colleges and universities need to do more to provide gender and sexual-orientation informed, creative, interactive and context-based approaches to consent education. Additionally, consent education should be tailored to the unique needs of specific subgroups, including cisgender heterosexual men and asexual students who had the lowest level of consent understanding in this study. Such an approach is needed to support college students to enjoy mutually respectful, fulfilling, and fun sexual and romantic relationships.