Emma Moore’s 2010 research into social groups at a school in Bolton looked at the non-standard use of ‘were’ in sentences like ‘it was in maths, weren’t it?’. Her research looks at four groups:
Eden Valley girls - higher class, focused on school, lived further away from other girls, used the standard form (‘was’) almost all of the time.
Populars - not focused on school, engaged in rebellious activities. The group did not always use the non-standard form. But three girls were members of a higher social class – these girls did not use the non-standard form at all.