School suspension and expulsion during adolescence are associated with multiple adverse outcomes such as an increased likelihood for mental health issues, a greater likelihood of alcohol and substance use, and involvement with the criminal justice system. Establishing school disciplinary policies that appropriately sanction unlawful drug use but that do not put youth on a trajectory toward involvement with the criminal justice system is complex. The “school to prison pipeline” has increased youth involvement in the criminal justice system, as schools have adopted “zero tolerance” for drug possession and use. These policies disproportionately affect youth of color, despite rates of drug use that are lower than white youth. In some states, the legalization of cannabis for persons aged 21+ is associated with a decrease in arrests among adults, but the evidence among youth is mixed. The relationship between these policies and risks of disciplinary action for youth remains unknown. To fill this gap, this dissertation utilized a mixed-methods approach. Quantitative methods examined changes in counts of cannabis-related disciplinary incidents (CDIs) as cannabis policies became increasingly liberal in Massachusetts from 2005-2021. We identified associations between district-level sociodemographic characteristics and CDIs. Semi-structured interviews were conducted with youth under age 21 to explore their perceptions of and experiences with school-based discipline for cannabis incidents. We found that counts of CDIs increased as cannabis policies became increasingly permissive. We also found that for every 1% increase in a district’s percentage of male students, English language learners, and students with a disability, the CDI incident rate increased. Qualitative findings demonstrated that cannabis use in schools is common, however schools respond to these situations in differing ways. Students called for open communication about the risks of cannabis use, without utilizing an abstinence-only approach. These studies shed light on a potential unintended consequence of cannabis policies: as policies have become increasingly permissive, counts of CDIs have increased. These findings provide critical information for policymakers who seek to mitigate potential harm from cannabis policies upon youth. Cannabis policies should be updated to incorporate guidance for educators to explore disciplinary alternatives that do not result in suspension and expulsion.