Update 6/2013: This post from 2008 is one of the most popular on my blog, due to Pinterest. I just learned that Joy (the author of the fun books below) passed away in 2009. Please read more about her here.
I got these books by Joy Sikorski off my bookshelf downstairs and I'm going to set them out in a basket with some colored pencils for some summer doodling fun...
How to Draw a Clam
How to Draw a Radish
How to Draw a Cup of Coffee
If you aren't familiar with Joy's books, here's a sample drawing lesson...