It'll be fine! I know from when my sister was in first school, but the school had a couple a couple of evenings (Sorry if I've repeated something, there's an ad in the way!) and they will teach you the methods that your children will learn in maths as they are different to what my parents learnt at school, so you will be able to find out what they'll be taught and how to help them if needed and also from what I've heard from Internet friends, but we don't get as much homework as children do in the states, and the teachers are there if you have any worries about your kids!
Also if you live in a city, then finding kids around you shouldn't be too hard, I don't know anything about Stirling, but if you look on a map then you may find roads that look nearer than they are thanks to cut-throughs. (I know there's some round where I live, but then I live down the other end of the country in a small town.)
Good luck to your children on their first day! (It's in a couple of weeks right?)