We've been using the Harcourt Family Learning Complete Curriculum books with our kids, including one child who's disabilities make reading and math pretty darned hard.
I'm happy with them. Amazon.com has a pretty good list of the books. The books were published by "Spark Publishing" (Flash Kids), but their web site is gone. I suspect they're no more. I can't find any evidence anyone else is publishing these.
The reading and math exercises are interesting enough and quite polished. The Grade 3 level readings are reasonably interesting to our 11 yo boy; it's tough to find that kind of age interesting/readable combination anywhere else.
Recommended if you can find 'em! We have the "complete curriculum" for grades 1, 3 and 4.