Hi!
Definitely look at our website for The Singer's Theatre. If he likes musical theatre, it's a great fit for any experience level starting at age 9. Go to www.thesingerstheatre.ca and look at the Junior Ensemble for ages 9-13.
If your son doesn't like to sing, you could try Lost and Found theatre or Theatre and Company for kids programs. At his age, you could also consider a choir or dance class (they all go together eventually!).
Good luck!