That may be true, but for students in grades 1-6 - at least for Math - that is no longer a valid excuse. We have purchased a license for the online component of our Everyday Math curriculum which means that by clicking on https://www.everydaymathonline.com your child can access his or her reference book which has everything he or she needs to review, to help with homework, or to study for a test. Our 8th graders taking Algebra 1 have a similar system which can be accessed at www.algebra1.com.
To use these online resources, your child will need the password they were given. In the event that they don't remember it, feel free to contact his or her teacher who will gladly let you know what it is.
These links will also be added to the sidebar of the blog so that they will be easily accessible even after this post gets buried in the archives.