Be grateful for B-minus? (5)

I believe the answer is:

bless

'be grateful for' is the definition.
(bless can mean to celebrate or be thankful for)

'b-minus?' is the wordplay.
'minus?' becomes 'less' (I've seen this in another clue).
'b'+'less'='BLESS'

(Other definitions for bless that I've seen before include "Glorify" , "Give benediction" , "Call God's favour upon" , "Make holy" , "Isn't that sweet?" .)

I've seen this clue in The Sun.

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