Update: the answer is 20 -- including all the people presenting....
Factors to consider...
Official class size is 30 (drops and odd things made it small...).
Class time is 7:45. We have no dorms, thus no on-campus students.
Today is a presentation day -- 5 students (one group) will be presenting something that is worth nearly 1/3 of their grade (I'm assuming most of them will make it)
The rest of the class will not be responsible for knowing the material, but they will do a feedback sheet worth small points.
the biggie --- we have 6-8 inches of new snow and it is cold and windy outside.
Go ahead and put your guess in comments --- (yes, even you Sunshine, but you have to post it before 7:45) ---