At Leaving Certificate Level, as well as offering non-exam subjects such as PE, Religious Education and Careers, Sligo Grammar School offers the following subjects:
- English
- Irish
- Maths
- History
- Geography
- Biology
- Chemistry
- Physics
- Agricultural Science
- Home Economics(Social and Scientific)
- Art (and Craftwork)
- Music
- Design and Computer Graphics
- Applied Maths
- Spanish
- French
- German
- Business
- Accountancy
- Construction Studies
- LCVP
- LCPE
CASD (Climate Action and Sustainable Development)
Leaving Cert students 2015