Schedule Changes Give Everyone ADHD

I don't know if this happens in other professions, but I've been in enough schools to know it is universal for education.  When there is any change to the "normal" schedule, everyone becomes ADHD.

I am in an area of the country that doesn't get a lot of winter weather; so when we do, we overreact just a bit.  School is sometimes called off altogether for a half inch of snow.  Typically, we get more ice than snow, which is a different thing.  A quarter inch of ice is worse than any amount of snow when it comes to driving.

My least favorite call in all of this is the two hour delay.  I would rather be at school all day or not at all than deal with the chaos of the two hour delay.  It shortens our class periods to 30-35 minutes.   Students believe this isn't enough time to accomplish anything, so they come in expecting to do nothing in every class.  Teachers know this is only 15 minutes shorter than normal, so we should be able to get some things done.  It changes lunch times and eliminates or daily snack time (because you just ate breakfast an hour ago, for heavens sake).

Listening to us on these days, you would think that we had been set on another planet with no instructions at all.  In reality, it is only a slight change, but the perception is that EVERYTHING has changed.  Furthermore, it happens EVERY time.  Last year was a particularly strange year, in which we had six days off for weather, two early release days, and four two hour delays.  You would think by the fourth one, we would all know when to go to lunch, but we didn't.  We were still all in a tizzy trying to figure out where to go next.

What is it about a change in routine that gives kids and adults alike the attention span of toddlers?  Does this happen in the animal kingdom?  If you walk your dog at a different time, do you throw off his whole day?  Does it make them confused about when they are going to eat?  Someone should get a grant to study this phenomenon.