Ordered out, disrupting test in class (8)
I believe the answer is:
tutorial
'class' is the definition.
(I've seen this before)
'ordered out disrupting test' is the wordplay.
'ordered' is an anagram indicator.
'disrupting' is an insertion indicator (inside letters 'disrupt' the flow of outside one).
'test' becomes 'trial' ('trial' can be a synonym of 'test').
'out' with letters rearranged gives 'uto'.
'uto' placed within 'trial' is 'TUTORIAL'.
'in' is the link.
(Other definitions for tutorial that I've seen before include "Conference" , "University lesson" , "Session of intensive teaching to an individual or small group" , "Session with a private instructor" , "Period of teaching as from college lecturer" .)