Homeschooling Doesn't Have to be expensive.

I have spent TON'S of money on homeschooling curriculum over the years, and have realized that most of it was a big waste.
I can't tell you how many things I have turned around and sold because it didn't really work for us.
If you are looking for ways to save money on your homeschool curriculum, the easiest way is to be very careful of what you buy in the first place.
Do your research, and make sure it will fit your families needs, and that you aren't just buying it because it worked for someone else.
Each family is different.
What works for some, won't always work for others.

As far as curriculum goes, I usually wait until Mardel has their Teacher Appreciation sale, and get it then. OR, I wait until there is a sale online.
I have moved away from textbooks recently, so that also helps.
I am trying to incorporate more living books into our homechool.
For school supplies, I wait until the few weeks before school starts, when all the stores have all of their sales, and then I stock up!!!
I only buy crayons at $.25, and markers for $1, colored pencils for $.50, etc...
I grit my teeth at paying full price for school supplies.

A BIG way that I save money is to shop the garage sales and the thrift stores.
I can not tell you how many books I have obtained over the years this way. I love getting a great book for a quarter! lol
I also look at www.christianbook.com in their clearance section, and I can get books there for less than a dollar!

I love CurrClick, and Homeschool Freebie of the Day! They both have great freebies, such as e-books, unit studies, lapbooks, and much more.
Also I look at Border's in their bargain books section. Here is where I have gotten most of my science/ Nature books, like books about weather, insects, trees, wildflowers, butterflies, etc...
We also have Hastings here, and they have great bargain sections also, AND they have used books, which are much cheaper.
Of course, you can be on the lookout for when other homeschoolers are selling their stuff, just make sure it is something you really want before buying it.

And don't forget the library. You can obviously get books for free there, unless you forget to take them back and get late fees! HA
I have been building my library for a couple of years now, mainly through garage sales and thrift stores, and I have thousands of great books now. 
I really don't like going to the library, so I have made my own!
You can too! It just takes a little time and creativity, but it can be done!!!
Good Luck!