Bad grades get evenly distributed (9)
I believe the answer is:
staggered
'evenly distributed' is the definition.
'staggered' can be an answer for 'distributed' ('stagger' can be a synonym of 'distribute'). I'm unsure of the 'evenly' bit.
'bad grades get' is the wordplay.
'bad' indicates anagramming the letters.
'grades'+'get'='gradesget'
'gradesget' anagrammed gives 'STAGGERED'.
Can you help me to learn more?
(Other definitions for staggered that I've seen before include "Arranged to take place at intervals" , "Gobsmacked" , "Deeply shocked or walked unsteadily as if about to fall" , "Amazed" , "Moved unsteadily, being deeply shocked" .)