We do our afternoon dismissal online. Personally, I love it. It's silent so it doesn't disrupt anything we might be doing (usually me reading poetry to the kids) and it's in print so I can look back if I'm not sure a bus has or hasn't been called.
As I do occasionally have to be out of the classroom I have two students who go to one of our computers and tell us when any new group is dismissed. My two little guys do a great job at this. At first I had dismissal open on my computer too, just to check. They've got it down now.
There is one small snag. Right there, under the '3:15 WALKERS' is the bit that throws them each day.
Every day they call out "Buses 2 and 7 are dismissed!" (or sometimes "Buses 5 and 7" depending on their perspective). Next week we're going to have to look at this carefully. It turns out we have a Bus S. I didn't know that. Not surprisingly my kiddos clearly don't know that.