<p>Mathematics often acts as a gatekeeper for students, particularly minoritized and underserved populations in racialized contexts. However, few studies in Canada have examined the experiences of Black learners in mathematics. In the 2020–2021 school year, Ontario ended the practice of streaming grade 9 mathematics due to the disproportionate placement of racialized, especially Black students in the Applied or Locally Developed streams. Guided by the theory of antiblackness, I argue that mathematics learning spaces are wholly antiblack. That is, though destreaming grade 9 mathematics is a step forward, additional barriers still disrupt equitable mathematics learning for Black youth. This study explores these barriers through interviews with eight Black learners in grades 10 through 12 living and learning in the Greater Toronto Area. The findings reveal that Black youth face pressures to prove their smartness in mathematics, the racialization of mathematical ability, lack of Black secondary mathematics teachers, and silence in secondary math classes that impedes discussions on social issues. I conclude by offering pedagogical implications for fostering an inclusive and supportive mathematics learning environment for Black students.</p>