Find your child's grade level on Amazon. I like how these books slowly progress through different topics and explain it well enough that I don't need a teachers manual. The pages are colorful and there is plenty enough practice that they can master it before moving on. (Also, they have an entirely separate practice book you can buy for a few dollars to get even more practice, if you need it.)
Other books we are continuing to use from last year are the Focus on Elementary science books. I like these because, as you can see, they are for a broad range of ages, which means we can all discuss it and do projects together, but then the Bear can extend her learning with writing about it all.
The Bear started cursive last year, so she'll continue to work in this book. We love it because each upper and lower case letter corresponds with pictures from history she can color. So as she worked on forming the letters, I would read to her about that topic. (Examples are pyramids, Mayans, 7 wonders of the world, etc.)
We will also use the Maps, Globes, and Graphs workbooks. They start on Level A, and progressively get harder with each level. Our family especially loves maps and geography, so these have been a fun addition to our homeschool.
Some new books we're trying out for this year include "Mind Benders," Jenny Phillips' language arts homeschool curriculum, "Write Source series," and "Explode the Code."
The Bear was so quick to start reading that she basically went from reading Bob Books and using Starfall.com to reading leveled books in a few months. And from there she's slowly consuming more difficult books on her own. I really didn't have to do anything but teach her sounds and provide materials. Buddy needs more help, so we're trying out "Explode the Code" with him. I hope he loves it and it works! He's already sounding CVC words with a occasional difficulty, so I'm hoping the work book will help him along.
"Mind Benders" is mostly to help their thinking/analytical skills. I read good reviews about this on amazon, so I thought we'd give it a shot.
"Write Source" was suggested to us by the charter school (see this post if you're confused about how I'm homeschooling if my kids go to a charter school). Last year I didn't use any language arts curriculum for the Bear. She was very self motivated to practice writing through letters and song/poetry that I didn't see any reason I should push that for my kindergartener. However, since she is skipping the 1st grade this year, I figured I should give her something more structured to make sure she is up to snuff on her writing skills.
I have had the time to look through Jenny Phillips' language arts curriculum for kindergarten and I think it's going to be great for Buddy. It includes lots of phonics type exercises, writing practice and sight words. Her lessons often include analyzing art work too!