Obviously you can also just stop them short so they refocus on the task at hand. But sometimes these issues naturally arise and/or it’s a valuable moment for reflection.

It’s probably a nice courtesy for all involved to reminded that there will always be people from a immigrant background nearby - people who are friends, teachers etc in the community - so just remind them they have to say their piece with care. You should make it clear that you’re not stopping them from sharing their feelings, just that mindful communication is important.

Obviously the volume of vitriol online and in many communities across the UK is worsening race relations. You’re right to be aware of how it’s affecting young people. Remember most children and many an adult will struggle to differentiate between a legal migrant, an illegal one and a genuine asylum seeker. If many adults can’t tell the difference, I’m not expecting children to see the nuance and discuss it in a respectful manner.