A few non-intelligence related points.
First, I think Chancellor Nordenberg is doing the right thing by giving the green light to evacuate the buildings for every bomb threat, regardless of how trivial or unlikely they seem. This is a pretty ridiculous situation and is sucking up time and resources, but he's morally (and legally) obligated to defer to student safety first.
However, I have some concerns about the rest of the process. I think the investigation needs to be way more transparent than it is. These aren't state secrets, it's likely a bunch of troubled kids looking for fun. So when the Emergency Notification System warns of a "general bomb threat" that's ALL the information the students are given. Tell us more! Where were the threats found? What kind of writing utensil was used? Was it new or old writings? Did the e-mail threat lead anywhere? What was the e-mail address? Where does it lead? Are there any suspects or leads? What the heck are we supposed to be looking for?
Right now, the student body (and public) is in the dark on this. I understand some level of confidentiality is important, but until the student body is 100% behind this effort, it's going to continue to disrupt classes and cost the school an insane amount of time and money.