[This was from a year (or so!) ago... just now posting]
My youngest is doing a speedy study of R.E.A.L. Science - Life (level 1). It's young for her but we'll be supplementing heavily and I just absolutely love this curriculum to fill in classification gaps before going into high school science [which she'll be starting in the Fall - ACK!]. I wish we had a level 2 but, oh well, we'll make it work :).
Here are some free online coloring pages in a random order (or it'll never be uploaded!). They recommend Color Anatomy by Christine Becker. We don't have that book and we would probably want more detail anyway so I started scouting around online.
Variety of Biology coloring pages:
Used to label her diagrams of plant and animal cells:
The Basics of Cell Life with Max Axiom, Super Scientist (Keyser)
Random Body Parts: Gross Anatomy Riddles in Verse (for fun!)
Magic School Bus videos (of course!): Goes Cellular (in the Super Star Power DVD); The Human Body (3 episodes in this video)