I think that having a puppy makes you very aware of your environment and the potential lessons you can teach the pup. Like balance, for instance!
Strange surfaces are another - I'll make Gummi go onto any strange thing I can find.
There was a little balance lesson in there, too, but less pronounced than on the log.
Any place/object you always introduce your puppy to? Or other important lessons you always remember? Please tell us about them, it's always nice to hear what others think and get new ideas.