I’m right there with you — it is hard to know how to make the biggest difference — but raising your daughters right is huge, and someday they will also vote and make their own difference. The “self segregation” thing in schools is also hard (still today), but on our club gymnastics team it’s always been all for one, and one for all. And I was proud of my youngest for joining the LGBT club just because a lesbian friend asked her to. These extracurricular groups help improve the mingling; don’t know if you have any good options near you. Also, I’m not sure what the “right” age is for them to start attending protests, but mine are certainly old enough that when they asked to come along I thought it was a good idea.
I am hopeful like you that the kids will break the mold. My 16-year-old says with great confidence, “Other than those Trump-loving white boys, nobody my age cares about anyone’s race / sexual preference / etc.” Of course when I was her age, I thought the same thing. But I’m trying to set a better example than my family did, and I imagine you are, too (my parents were actually pretty open minded, but didn’t actively push social change). Every bit helps.