One class supports small change, to a degree (10)
I believe the answer is:
centigrade
'to a degree' is the definition.
I can't tell whether this definition defines the answer.
'one class supports small change' is the wordplay.
'one' becomes 'i' (Roman numeral).
'class' becomes 'grade' (grading is a kind of classing).
'supports' means one lot of letters go next to another (bottom letters provide a support for the top ones).
'small change' becomes 'cent' (I've seen this in another clue).
'i'+'grade'='igrade'
'igrade' put after 'cent' is 'CENTIGRADE'.
Can you help me to learn more?
(Other definitions for centigrade that I've seen before include "C" , "measure of warmth" , "scale" .)