✔ 最佳答案
If he/ she's from the US, then as a sophomore next year, I recommend preparing for SAT/ PSAT.
Most people start preparing in junior year, but then if a kid start preparing earlier, it'll greatly affect his/ her future.
In Hong Kong you can go to America Prep, Kaplan, and Princeton Review for courses.
Or you can choose sports. Basketball, soccer, football etc. Not YMCA or kids stuff though as the 15 year old is no longer a youngster/ kiddle.
If the kid is in Hong Kong, why don't you let him/ her try some Chinese stuff? People like them always like martial arts, calligraphy etc.