Proper stars in schools (9)

I believe the answer is:

primaries

'schools' is the definition.
(primary schools)

'proper stars' is the wordplay.
'proper' becomes 'prim' (similar in meaning).
'stars' becomes 'aries' (constellation).
'prim'+'aries'='PRIMARIES'

'in' is the link.

(Another definition for primaries that I've seen is " schools".)

I've seen this clue in The Times.

Want a hint initially instead of a full solution? Install my app