iPad & iPod Devices - How have you deployed them in your school?

Looking for easy way to deploy iPod and iPad devices in schools especially with management of apps. How are you setting up the iTunes account on the devices? Our issue is having to provide credit card information even for free apps. Are you locking the devices down so teachers and students cannot access the internet or iTunes?
Also need ideas on how best to use them with students. If you have suggestions or links to some good education apps then please share! Any thoughts, ideas or resources will be greatly appreciated!