I've never really thought about it. DDs school isn't very diverse I suppose, but she does have lots of 'different' friends.
DD 'looks' as English as they come, but is actually Welsh and has a mixed race father. I am a complete mongrel as I am from a travelling background and couldn't tell you what ethnic mix I am. I look white/boring English type, but know that I have a blood relative from Spain and another from Eastern Europe.
In her class she has:
1 Romany girl
1 Polish girl
1 Spanish girl (actually I think she might be from Argentina but DD says she is Spanish)
2 English girls
They are all white.
Of the 15 boys I only know a couple, but one is Irish, one Scottish and I think the rest are all English. They are all white.
There is a good mix of 'circumstances' though. From living in a caravan and travelling around the county (her mum has actually just settled), to children living in council/HA, to army accn (us), to box standard private rental/own housing and at the top end two kids who live in houses with ponies and paddocks etc!
The whole school is like that tbh a real mash up of the 'haves' and have nots'. We are probably somewhere in the middle. You can see the 'cliques' in the playground though - mainly where the women are concerned. The men are all friendly (DH has befriended one chap who owns a string of gyms/sports centres and another friend who uses DHs gym membership 'on the sly' because he can't afford it himself - they all get on like a house on fire).
I grew up in a predominantly white area and had very few non-white or even non-English friends. However now I have a mixed race husband, welsh ILs, and amongst my friends I have: numerous white/Brits, 4 black/Brits, two Chinese, one mixed race Chinese/Brit, one black Jamaican, one black Ghanaian, 2 Nepalese and one white Canadian. Two of my friends are 7th Day Adventists, 3 are Muslim and the rest I wouldn't have a clue!
They all bring different PsOV to the table and I enjoy spending time with them all.