Education.com is a very helpful site for creating your curriculum.
We're making up our own as we go along, but I want to make sure I don't leave out any of the "standard" basics. Every month or so, I revisit this site to check that we're getting everything in. We could probably do everything on the list in three months, so I don't worry too much. Our curriculum doesn't revolve around it, I just make sure to include most of it - we don't include areas that aren't relevant or of interest to us.
Just go to the site and look for "Browse by Grade" on the right-hand sidebar. Open your child's grade and they show you subject-by-subject content. It's very clear and to-the-point. You can see what the standard curriculum is and then create your own, including as much of the suggested content as you want and ignoring what you don't want.