Make sure you are in the Sandbox for training!  There are three ways you can tell that you are in the Sandbox and not in the Live database.  See screenshot below:

1. On the login screen
2. In the Action Bar
3. District Announcements

IMPORTANT: Just like a sand castle on the beach, this environment can be wiped out at anytime by a wave or two. In our case, we refresh the SANDBOX with current data from time to time without warning, so don't do too much work in here expecting it to be saved for a long period of time ... it won't be!