Creativity in Belfast, potentially on the rise in school (5)
I believe the answer is:
train
'school' is the definition.
(I know that school can be written as train)
I don't understand the remainder of the clue.
(Other definitions for train that I've seen before include "Line of railway cars with locomotive" , "Learn a skill etc. through practice" , "Prepare for public transport?" , "Choo-choo or part of wedding dress" , "Prepare oneself by exercising" .)