Ran pupils' gymnastics in the old style (5)
I believe the answer is:
loped
'ran' is the definition.
(loping is a kind of running)
'pupils' gymnastics in the old style' is the wordplay.
'pupils' gymnastics' becomes 'pe' (Physical Education. I am not sure about the 'pupils'' bit.).
'in' means one lot of letters goes inside another.
'style' is an anagram indicator (style can mean to shape or design).
'old' anagrammed gives 'lod'.
'pe' placed within 'lod' is 'LOPED'.
Can you help me to learn more?
(Other definitions for loped that I've seen before include "Ran with long strides" , "Made strides" , "Walked with long strides" , "Bounded along" , "Walked with a long bounding stride" .)