It is possible!! I did a little research last night and found some interesting free curriculum for our home school!
LearningPathways is a free online curriculum for K to 5th grade. Lots of great stuff here! I actually started using this site just this year and the kids are loving it. They are doing really cool projects and experiments as well as watching really fun videos online. A lot of work was put into this site and anyone who has tried to research a topic on their own knows what a gem this is! http://www.learningpathways.com/
Another website I found was learnLatinonlinefree. This was a video and worksheet Latin curriculum all online with no textbook needed. I think it is best suited to high school kids, but would be of interest to anyone wanting to learn more about Latin. http://www.learnlatinonlinefree.com/
Music lessons is always a hot topic at our house. They are just so expensive and add up quick when you have a large family. I looked around and found pianolessons online for free. These are video lessons with music reading and ear training. Plenty of lessons to keep anyone really busy on the piano for a long time. http://www.pianolessons.com/
Reading is a huge deal in our house. Most of my kids love to read. We have used a wonderful website called starfall for phonics and reading for several years and the kids love the animations and games. http://www.starfall.com/
Last night I came across another free reading website simply named learntoreadfree. It looks to have some fun games to engage the kids. The concept is Montessori based and is quite repetitive. http://www.learntoreadfree.com/
BookAdventure is another great reading site that is sponsored by Sylvan Learning. Book Adventure provides grade appropriate book lists. The kids choose a book, read it , then take an online test over the book to earn points which they can redeem for prizes. Parents can customize the prize board, which makes for some fun incentives in our family. http://www.bookadventure.com/