Sweets and drops the head confiscated outside class (3-5)
I believe the answer is:
Here is my best explanation:
'sweets' is the definition.
'drops the head confiscated outside class' is the subsidiary indication.
'drops' becomes 'palls' (palling is a kind of dropping).
'the head confiscated' means to remove the first letter.
'outside class' becomes 'orts' (I can't explain this - if you can you should give a lot more credence to this answer).
'palls' with its first letter removed is 'alls'.
'and' is the link.
(Other definitions for all-sorts that I've seen before include "See 10", "Things of various size, shape or colour; sweets", "A mixed variety as of liquorice sweets" and "Mixture (of liquorice sweets?)".)