Students are offered a wide selection of sports administered by qualified coaches. Sporting codes include: water polo, swimming, rugby, hockey, athletics, tennis, netball, indoor hockey, cross country running, tennis, golf, basketball and cricket.

Reddam House Constantia also provides a thriving and vibrant cultural offering, with specialist teachers in the fields of art, drama, dance, design and music. These cultural specialities are  offered as formal subjects of study in the College from Grade 8 to Grade 12. The cultural department also oversees the annual drama productions and musicals; four dance genres (ballet, tap, hip-hop and modern); music evenings; one-act plays; a debating society; chess club; dance choreography evenings; design and art exhibitions; and various music and language eisteddfods. The dynamic music department boasts an award-winning orchestra, a baroque ensemble, several bands, and a vocal ensemble.

All students must participate in extra-curricular activities; this builds both school spirit and a sense of belonging and meaningful contribution to the broader school community.