I am big on using public domain material in our homeschool. I often use several, PD (public domain) books each year. I touched briefly on this subject in the post about homeschooling on one income. Today I want to share a free site with you that has been a great help to me for several years. You can find public domain curriculum for grades K - 11 at An Old Fashioned Education.
Very Convenient
You can just follow the curriculum as is. As you'll see when you visit, everything is conveniently laid out for you. An
Old Fashioned Education even includes 40 week schedules for each grade.
Depending on how you homeschool, this may be of help to you. When
I first began homeschooling I used to try to adhere to precise
scheduling. But ultimately for us it turned out to be more of a burden
than a help. So, today I would use this more as a guide.