Are students from the other schools automatically enrolled?

From BbWiki

Students are added as we receive information from the other schools' registrars. It can take a week after drop/add period ends before information is sent from other schools.

If you need to give students immediate access, you may wish to manually enroll them using the Enroll User tool in the User Management section on the right side of your control panel. To add a user, search by last name or username and check the box to the left to select the user. Click Submit and the bottom of the screen to enroll the selected user in your Blackboard site.