When it comes to lesson plans, I like things clear, concise and all inclusive. Tall order I know, but convoluted themes make me insane. Since we have been planting a garden, I've been working my son's lessons around that theme.
The Missouri Botanical Garden website has a very nice all inclusive site about the Biology of Plants. Everything you need for basic elementary school age lessons are there.
Plus they have teacher plans you can download to expand on the ideas.
You will also find other educational DVDs for sale on
the Botanical Garden website.
Such as: The Secret Of The Pond and What's In Your Backyard. I love the layout and simplicity of these sites. There is a wealth of information here!
*graphics credit to mbgnet.net