Short Bus

There is nothing this funny about being on a train but it seemed like everytime we went anywhere we ended up like this...laughing so hard we couldn't breathe. One of our rides ended with us laughing so hard we were seriously crying while a trainful of people crowded by our seats watiting to get off the train despirately wanted to know either:
1. What in the world could have happened that was so stinkin' funny or...
2. Why they let two kids from the short bus take the train by themselves.