Our very own nature journal (spiral bound sketch book), combined with the internet and/or our encyclopedias. I know there are a few books you can buy that have lots of nature journal tips and ideas (dunno any titles tho). Ds draws the nature he sees, animals, insects, flowers, leaves, etc., then we learn about them when we get back in the house. He'll write their name and a few facts he really liked about them in the book next to the drawing. We occasionally take it to the lake in town and walk the trail with dd in the stroller. Art, science, writing, and pe, all rolled into one.
MaryAnn Kohl's books are great. She has one entitled Science Art, I believe, as well as Math Art, Preschool Art, and lots more (for some reason mine aren't on the shelf where they belong, so I can't see the titles...)
For drawing there's Drawing With Children. Dd enjoys drawing, so I also got some of the Draw-Write-Now books. She skips all the handwriting.
Let's see, the woman who did the Un-coloring Books did one entitled Young at Art for preschoolers. It is absolutely fantastic.
Janice VanCleave has many, many books about science. Some are geared mores towards preschool to around 1st grade, others for older kids. I happen to prefer the ones for preschoolers.
I have a weakness for books with lots of colorful pictures, so Kingfisher and DK books litter our bookshelves. It's nice to have some encyclopedia-like books and/or field guides as you develop interests in various subjects. One of my kids likes to browse through books like this and just absorb info.
None to trade or sell...most of the ones I've mentioned (except Draw-Write-Now) are available at our public library, though, so you might see what's available to you that way.
This is a science book that also reinforces/teached the alphabet through a science concept and or experiment with each letter. it is Awsome! It is by Andrea T. Bennet and James H. Kessler, and put out by McGraw-Hill.
We also have another one called learning to be a scientist, by the Science Works for Kids Series put out by Evan-Moor. It says K-1 on its cover.
My favorite books are the Kid Concoctions series. I first saw them on PBS and then I checked them out at the library. They have a lot of fun and easy activities that don't require a lot of materials. We have been doing a couple of activities from the book each week. It's great for all my kids (8,5 and 2). We're going to do the popcorn art today