Can you look up the subject requirements for 3rd grade on your state website and generically go through the requirements. The test will not be exactly what is in the textbook. Also if you have used book stores in your area look in there for old textbooks. You can even find teacher's textbooks that has the standards outlined. If this doesn't work you could go to a local university in your area that has a teaching program and use their library. You might be able to check out the textbooks from them. But I wouldn't get too locked on having the exact textbook used in class. Just work with the state guidelines. Anything that is specific will be easy to teach and the more generic ones are reinforced over all grade levels.
