The engines are in Idle, there is no run-up in the checklist...however, you may have had this misfortune to be following slow students. Some IP's were extra slow too (i.e .liked to watch students go slow and excruciatingly methodical)...so if you get a slow student and an IP who likes slow students, you might be there a while.
Also, the ATIS also could have just changed and he was making the student do manual Take-off data with the spaghetti charts. In general, if you see a jet with a Laughlin tail taking a while, "Learning is happening."