In 2002, Jane Margolis and Allan Fisher's research presented computer science (CS) education as a clubhouse for males that resulted in females being left out of the CS loop [1]. The researchers identified several influences contributing to a gender gap in computing education and they called these influences the doors, walls and windows of the computing clubhouse. In order to determine whether or not a gender gap exists in Ontario high school CS, this research analyzes enrollment figures provided by the province and concludes that during the 2017-2018 school year, females made up only 26.6% of students enrolled in the grade 10 course, 20.4% of students enrolled in the grade 11 courses, and 15.7% of the students enrolled in the grade 12 courses. Enrollment numbers from 2009 to 2017 revealed a similar pattern. The research also explores the impact that a gender gap may have on economic and educational opportunities for underrepresented groups in Ontario and identifies scalable solutions and frameworks [2] that may help dismantle the doors, walls, and windows of high school CS education in Ontario. This research is timely considering that the Ontario Ministry of Education recently announced a strategy to revise high school CS curriculum [3] while Canada's federal government announced an additional $60 million of funding to support the CanCode K-12 coding initiative [4]. Research seeking to provide insight into existing gender gaps in CS education and potential frameworks that may help improve diversity and inclusivity in CS curriculum and policy initiatives is critical considering the potential impact and missed opportunities that result from a CS student population and workforce lacking in diversity.