The following subjects are available to all Senior Cycle students in Gaelcholáiste Charraig Uí Leighin;
| Core Subjects | Option Subjects |
| Irish | Business Studies |
| English | Accounting |
| Maths | Engineering |
| Spanish | Construction Studies |
| Career Guidance | Art and Design |
| Religion (Non-Examinable) | Design and Communications Graphics |
| Geography | |
| History | |
| Music | |
| Computer Science | |
| Leaving Certificate Physical Education | |
| Biology | |
| Physics | |
| Chemistry | |
| Home Economics |
All Option Subjects are offered as tasters in Transition Year., and are discussed during Career Guidance class. Students pursue 4 Core Subjects of Irish, English, Maths and Spanish, along with three Option Subjects from those listed above for their Leaving Certificate. These Option Subjects are chosen during Spring of 4th Year.
