Despite high survival rates for many adolescent or young adult (AYA) cancer diagnoses, the psychosocial, academic, and vocational repercussions for survivors are profound and enduring. Hospital systems are able to address many AYA needs, but the ability to provide the human connectedness and knowledge that drive long-term school and career planning is lacking. This study assessed a group of AYAs who have or had cancer (n = 108, 54% female, 71% white, mean age 20.6 ± 4.4) to determine the school, career, medical, emotional, and psychosocial needs that are not currently being met by hospital staff and support networks. We identified the most common unmet needs of AYAs, differences between needs of AYAs in active treatment and survivorship, and the role of a career-focused mentoring program developed by the nonprofit organization Connecting Champions (CC) to address the array of unmet AYA needs. We found that the most commonly reported needs were all related to career and school, and that the top needs did not differ significantly throughout the cancer journey. These findings suggest that career and school-based needs are a high priority for AYAs, yet social isolation can make the necessary people or resources inaccessible. The CC mentoring program was reported as effective in attending to unmet needs (with an average score of 95.1/100) and can be a valuable resource for hospital systems, nonprofit organizations, and health insurers to provide personalized, career-focused support to AYAs during cancer treatment and survivorship.