I think that older teenagers are more accepting than other "groups".
I think the younger teens are much more judgemental. 16+ from my experience are mostly fine, under that they are douches. i was bullied for 5 years of school for being German. that obviously makes me a Nazi who wants to rid the world of Jews. And that's just for my mum being german, not even me. But then i went college with 16+ year olds and they are mostly very mature. then again these are the people who decided to carry on education, so maybe that's taking an unrepresentative sample.
i think the elderly are much more likely to be racist. case in point - I was standing at a bus stop, the bus arrives and two old women walk out. There is a black lady in the qeue in front of me. One elderly woman says to the other " Damn it i hate those blacks. wish i was alive when slavery was around" I was just like Holy shit did she say what i think she said?
Then i told my mates, who are also teens, and they had pretty much the same reaction. and then you have the likes of people who go around saying " f'ing polish taking or jobs, damn muslims, etc. etc, send them all back to their country" and a lot of them are 30 somethings with a beer belly, who haven't had a job, and living off dole money.
I also think teens are much more accepting of gays and lesbians.
Also i do know that not every elderly person is racist, and that not everyone who hates "foreigners" is 30 and has a beer belly. they were more examples.