To work out how many peas you need place the dried peas into the empty (soil free) tub of your choosing - ensuring the peas are densely packed in one layer only.
Empty the peas into a glass of water to soak overnight. Don't skip this step. We did the first time round and the peas never came to anything.
The next day drain your peas and line your tub with a layer of compost or cotton wool (perhaps a centimetre thick)
Add your peas.
Leave on a sunny window ledge, and water when the compost or cotton wool feels a bit dry. That's all it takes to grow pea shoots - it really is as easy as that! You could cover them with a clear plastic tub (again, like a fruit tray) to trap heat. It should only take about five or six days to get to a good height, ready for eating.