I take attendance and count tardies. If you are going to miss, I want to know before class starts if at all possible. A few tardies don't matter, but if you're habitually a few minutes late, I'll get annoyed and your grade may reflect it. Having a student come in after the lecture has started disrupts the learning of the rest of the class; I understand about parking, buses, trains, etc. and don't mind a few tardies. If you're going to be an hour late, please come to class anyways. You'll get to see the slides and specimens, I won't count you absent, and you'll have a chance to copy notes from someone. If you do miss class, I'm almost always willing (short of an "I didn't feel like it" excuse) to take extra time and open the lab up for students outside of class; ESPECIALLY if the students contacted me before or shortly after the absence to notify me. If you decide to make it up a week later, I might be a bit reluctant. ;o)
