Where schoolchildren are put in the picture? (6)
I believe the answer is:
inform
'where schoolchildren are' is the definition.
The definition suggests a singular noun but the answer is not.
'in the picture?' is the wordplay.
'the picture?' becomes 'form' (I can't justify this - if you can you should give a lot more credence to this answer).
'in'+'form'='INFORM'
'put' is the link.
Can you help me to learn more?
(Other definitions for inform that I've seen before include "Notify or tell" , "effective" , "Put wise" , "Tell (someone)" , "Impart knowledge" .)