You take one of your Great-grandparents name, although I heard it as grandparent, and the street name of where you first lived,or primary school name.
That makes me either Florence, or Ellen North. Using my grandmother's name as I don't know what my great-grandmother's were called.
My children would possibly have to use their primary school name for the surname, as I don't know if Slyne sounds right as a surname, unless they were Dickensian baddies.
They would be Doreen or Margaret Bolton-le-Sands, and James Bolton-le-Sands and Alan Bolton-le-Sands. I think I'd rather have them as posh Dickensians than baddie ones.
Work your Dickensian name out and leave me a comment with it, if you want.