I think a lot of the time it depends on how things affect you directly, doesn't it? I personally live in a very quiet, predominantly white Scottish town. The reason our primary schools are starting to bulge here isn't foreign immigration. It's because of the new 4/5 bed family orientated, affordable housing estates that have been built here over the last 10 years. We've had a baby boom and there's been an influx of Scottish/British families move into the area, which is wonderful, but the council haven't had the common sense/funds/space to build another, much needed school. Migration has impacted the amount of available school places in my town, but it's impacted it because the council have failed to build another school. They seem to be under the impression the population hasn't grown since the schools were initially opened 
On the flip side of that, my sister lives quite close to London in an area that has seen heavy immigration and a massive baby boom over the last few years. Children living in her area are being driven left right and center to alternative counties sometimes, because there are not enough school places. It's an absolute joke. She, understandably, gets really angry about it. Not that 'immigrants' have 'stolen' the places, but that the government and local councils have allowed the immigration to happen without putting in place the necessary infrastructures to deal with it.
For us, we don't mind anyone coming to live, work and raise a family here. Come on in - we hope you love it here
That's not an issue at all. I think the bad feelings often stem from knowing that your own children are suffering or missing out because the numbers are out of control in proportion to the services that are currently open and available in your area. When people talk about immigration being a problem in this regard, very few mean that in a, 'Those pesky foreigners have snatched up all the school places again!' sense. I think what people mean when they talk about immigration impacting school places is just that - the numbers are too large in an area where the school places are likely too few. That is the fault of the government and councils.
Build what we need, employee who we need - give everybody a fair and equal chance to use the services we all work so hard to keep open and running. Then evict all the horrible little racists, dump them on an island and let them eat each other. Problems solved!