Place to play is small - also mine (7)
I believe the answer is:
sandpit
'place to play' is the definition.
I can't judge whether this defines the answer.
'small also mine' is the wordplay.
'small' becomes 's' (abbreviation - e.g. clothes size).
'also' becomes 'and' (both can mean in addition).
'mine' becomes 'pit' (as in a mining pit).
's'+'and'+'pit'='SANDPIT'
'is' acts as a link.
Can you help me to learn more?
(Other definitions for sandpit that I've seen before include "Play area; quarry" , "place where youngsters can play" , "Play area for small children" , "children may play here" , "Playground feature" .)