Schools, as social systems, may knowingly or unintentionally perpetuate inequities through unchallenged oppressive systems. This paper focuses on mathematics as a subject area in school practices in which inequities seem to be considered normal. Issues of racism and racialization in the discipline of mathematics are predominantly lived through the practice of streaming where students are enrolled in courses of different levels of difficulty. Such practice denies marginalized groups of students the full benefit of rich learning experiences. These issues should be of concern for activists, advocates, and allies as well as individuals and groups who are systematically and directly affected. The purpose of this paper is to make visible issues of racism and racialization in school mathematics to a range of stakeholders that include: school administrators, teachers, students, parents, education advocates, academics, educational researchers, and politicians. The ultimate goal is that the knowledge gained through this call to action will contribute toward eliminating social injustice in all school systems, particularly as it relates to skin colour, country of origin, culture, language, customs, and religion.