Well, we can't really help without the source. Do you have it hosted? If not post the code or something, I am sure I could help much easier if you do.
But just as a reference, are you using CSS? If not, that may be the problem, I find when I don't use CSS it can mess things up on differen OS/browsers.
Or, it could be that your home computer is messed up. I remember when my video card started to go out, it wouldn't view all pages correctly, blue was seen as a brownish color, etc. Or it could be the schools computer.