I found these books extremely helpful when homeschooling my older son. They are produced by Macmillan-Hill and they are practice workbooks. The files are in PDF format, and most are fairly large. There are three sets of books per grade level: On Level, Spelling and Grammar.
I found that the books are very good for teaching a variety of topics, to include: punctuation, sentence structure, literary elements, vocabulary building, reading comprehension, etc.
A full listing of the books, by grade level, can be found here:
I am still looking for something similar in math, and if I ever find it, I will let you know!