There are many opportunities for students of all years to represent Kirrawee High School in the competitive NSW Combined High Schools Knockout Competitions as well as other Interschool activities such as
| Baseball | Basketball | Cricket |
| Oztag | Rugby League |
Skiing and Snowboarding |
| Touch | Football | Futsal |
| Tennis | Water polo | Lawn Bowls |
| Squash | Netball | Volleyball |
| Triathlon | Rugby 7's | Mountain Biking |
| AFL | Equestrian |
Kirrawee High’s water polo program is very well established with many students also participating in external competitions. Kirrawee High has won the Boys and Girls Open and U/15 State Knockouts on many occasions. Kirrawee High has a strong sporting tradition. Teams are entered in a large number of state-wide knock out contests that have been highly successful. The school has had many outstanding individual achievements including NSW and Australian representatives and/or champions in swimming, athletics, football, futsal, gymnastics, cricket, water polo, softball and netball.
Each year Kirrawee has many students who represent the Sydney East Region at State Championships, particularly in swimming, cross country, athletics and water polo.
Students wishing to trial for a Sydney East team must see the Sports Organiser for details and complete an online nomination through DASH (a minimum of 2 days prior to the scheduled date) and then await school permission.
Each year the school conducts a swimming and athletic carnival. These are whole day events and are compulsory for all students. A one day cross country carnival is held for interested students. These carnivals are always a fantastic day together as a school community.