After remaking out school's site completely due to my mistakes I have now got everything up only to find that any user I create gets "kicked off" for lack of better words.

Here is the scenario:
1) user logs in (use can edit the home page)
2) user clicks on second page (which they have editing permissions assigned) they can edit ok
3) user goes to third page (which they have editing permissions assigned) they get the heave-ho and are logged out and need to log back in again to edit.

I have missed something in the permissions?

I have cleared the cache numerous times and no luck.

Thanks for any suggestions