Hi Belma! Wow - no replies and your post was from 2014! Well I'll be your first...
This particular issue was occurring on a weekly basis in G101 Mac Lab. It's only been working "for us" (not against us!) this year - 2017. So, to offer some insight into an ongoing, technological nightmare, there were several things I would do:
Prior to class:
1. Logon - this could take anything from 5 minutes, 20 minutes to never (being locked out of your own account!)
2. Ensure ALL hardware - keyboards, USB drives, projector, audio system - were functioning correctly
3. Verify that at least ONE student could log into their Mac
4. Verify that ALL websites that would be used in that learning session were ACCESSIBLE (that day!)
SOOOO....when the technology DID fail, I always had a "plan B" up my sleeve:
1. Going "old school" with Ear Training using an acoustic piano
2. Use the piano to explore, with students, a theoretical or songwriting concept
3. Get students to break into small groups to write a 30-second "jingle" using acoustic guitars
4. Heaps of other options...!
AFTER the event, I would always try to log a job with IT, providing them with as much information as possible (however, sometimes this wasn't always possible due to time constraints and/or jobs already having been logged).
I would also inform the students that I would be doing my best to rectify the problem for next time.
OK, that's enough from me Back to work!