MY gal was selected for Atistic Gym - not sure shld i enroll her for it???

too tough for a small Build like her???
heard required to practise 3 times per week when comes near to competition??
Spoke to her, she expressed her interest in it, however, im afraid might affect her studies?
The Gym on thursday 1:45 - 2:45, when do they do after that if they re waiting for sch bus to come at 4pm