School-based speech-language pathologists (SLPs) can play an important role in the recovery of children who have sustained a mild traumatic brain injury (mTBI). Two types of knowledge barriers are described here that impact the beliefs and ability of SLPs to respond to the needs of these students. Foundational knowledge is relatively stable over time, and encompasses basic definitions and understanding of the injury. In contrast, flexible knowledge addresses clinical management, including assessment and treatment, and should be regularly updated to align with current best practice recommendations. Clinicians are sensitive to this difference, seeking clinically applicable continuing education. However, general poor understanding of pediatric mTBI paired with rapidly advancing research in the field has led to widespread inaccuracies in both foundational and flexible knowledge. Suggestions are provided for educational initiatives and for advocacy of the role of SLPs in the care of students with mTBI.