When logging into any of the mac computers if you are prompted for a keychain select the middle option which I believe says "Create new Keychain."
It should never ask you again.
IF you still get prompted for the keychain on other macs or when trying to use an application do the following steps.
- click on "go" on the top bar
- click "utilities"
- click on "keychain access"
- on the top bar click on "keychain access service"
- click "preferences" on the drop down menu
- select the "first aid" tab
- make sure "synchronized" option is checked on
- log out
- log back in