I have two hermit crabs (Houdini and Shelldon), an ant farm, and a betta fish (sushi).  Houdini is so named because he escaped twice on different evenings.  We now have to keep a heavy book on top of his cage.  We would have loved to know how he was getting out.  He has since changed from his big shell back to his small shell, so maybe it didn't fit right.  It would be wonderful to observe how he did this.  I'd also like to track my ant farm from beginning to end because they make quite a bit of progress in one day.  It is difficult to get all the kids close enough to see.  If I get the camera, I will post pictures!