School head went ahead, getting winter transport (4)
I believe the answer is:
sled
'winter transport' is the definition.
(I've seen this in another clue)
'school head went ahead getting' is the wordplay.
'head' indicates taking the first letters.
'went ahead' becomes 'led' (led the way).
'getting' says to put letters next to each other.
The initial letter of 'school' is 's'.
's'+'led'='SLED'
(Other definitions for sled that I've seen before include "Vehicle on runners" , "Sleigh" , "Snow transport" , "Toboggan (mainly US)" , "Winter transport" .)