CCSD · Senior High
St. Mary's High School
10-12 · 111 - 18 Avenue SW
The methodology
The data behind this score
The Roost Rating weights AEAM above PAT, plus Roost field research, capped at 95. A missing source has its weight shared across the ones that remain, never counted as a zero.
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Classes and enrolment
Typical class size
- Grades 10 to 12
- 30Typical for these grades across CCSD schools: 28from 126 classesNot counted above: 4 classes with fewer than 10 students (Alberta does not publish their sizes).
Each figure is the middle class size in those grades for 2025/26, among the classes whose sizes are published. A class is one teacher with one group of students, so a group with several teachers counts once per teacher, and in junior and senior high each course section counts. The CCSD figure is the middle of every CCSD school's own figure for those grades, across Alberta's release.
Students enrolled
1,072 students in 2025/26 (preliminary)
Students enrolled each school year, 2016/17 to 2025/26
- 2016/17: 974 students
- 2017/18: 1,027 students
- 2018/19: 1,026 students
- 2019/20: 1,091 students
- 2020/21: 918 students
- 2021/22: 978 students
- 2022/23: 995 students
- 2023/24: 1,037 students
- 2024/25: 1,048 students
- 2025/26: 1,072 students
Enrolment moves with boundary changes, new schools nearby, the grades a school offers and how many children live close by. Most schools here had fewer students in 2020/21, the first school year of the pandemic.
Context only: these describe the school's situation, not how well it teaches, and neither is part of the Roost Rating.
Contains information licensed under the Open Government Licence – Alberta. Source: Alberta Education and Childcare.
Class sizes as of Nov 24, 2025Enrolment 2025/26 is preliminary: Alberta replaces it with final figures later.About these figures
Enrolment
How enrolment works
- Grades
- 10-12
- Address
- 111 - 18 Avenue SW
CCSD attendance areas give in-area families priority, not a guaranteed place. St. Mary's High School is your priority senior high only if your address falls inside its area — confirm yours with an address lookup.
Register through the Calgary Catholic School District.