NB The floating pea method is quite tricky. The cork slices have to be thick enough to float, even all the way across with a centrally placed hole so that the pea balances properly. I think you also have to be careful about which way up you place your pea. The roots are supposed to go through the hole but our root has wormed its way over the edge of the cork disc.
As well as the above mentioned two methods, he also tried germinating a bean by hanging it above the water. He used a very long wire tie - the sort they package toys with that make it REALLY difficult to get the toy out of the box. I wrapped the end of the wire round the neck of the jar for him and he needed a little help to push the wire into the side of a pre-soaked runner bean but was able to bend the wire so that the bean hung about 1" above the water. Look what happened :0)
He also had a lot of fun comparing soaked bean/pea seeds with unsoaked ones. He enjoyed peeling them and looking at the differences and similarities of the different seeds. He found where the roots and shoots will stem from and we talked about the seed being the first food for the plant.
I also got some ideas and activities from Seeds.
Both children pretended to be seeds growing - The Girl used to do this a lot when she was a toddler :0) So cute - they pull big smiley faces for the flowers! This led into a discussion on seed dispersion (ugh! bird poo spreads seeds!). We ate seeds - sunflower ones, planted some seed potatoes and looked at some games online.
And just for fun to go along with the bean theme
Kids garden - activities, printables, info, useful for plants & gardening in general
Seed site - lots of info and links to colour diagrams
BBC kids gardening - activities and experiments
Seed packet printables
Veg Seed Minibook
Bean plant to label printout
Bean growing cards to print
Good explanation of bean seed growth - not dumbed down
Books we've used to go along with this project;
The Golden Nature Readers - Book One
Enid Blyton's Book of the Year