Shine as a result of help turning up in class (7)
I believe the answer is:
radiate
'shine' is the definition.
('radiate' can be a synonym of 'shine')
'help turning up in class' is the wordplay.
'help' becomes 'aid' ('aid' can be a synonym of 'help'**).
'turning up' shows that the letters should be reversed in order.
'in' is an insertion indicator.
'class' becomes 'rate' (I've seen this before).
'aid' back-to-front is 'dia'.
'dia' inserted inside 'rate' is 'RADIATE'.
'as a result of' acts as a link.
(Other definitions for radiate that I've seen before include "Beam brightly, spread heat" , "Give out (light, etc)" , "Emit (light, heat, etc)" , "Spoke out" , "Emit rays; diverge" .)