I tried to catch the fish in the bottles, as mentioned by some others... I was sad that they swam away... :<
--Oh, oh! Here's a good one: you know the claimed 1:1 sword play that this game features? Well, I tested this right away after I borrowed the knight's sword from Eagus and was actually let down that it didn't work... I took my wiimote and pretended to stab myself in the chest with it. Er, it's not really a surprise that the game wouldn't let me, but I was still bummed about it. xD
I tried to fly my loftwing at night, from the Pumpkin Landing so that one guy wouldn't yell at me... Figures my loftwing was sleeping...
I tried using my items on people, seeing their reactions. Most amusing was bombing Gorko, using the gust bellows on random people, and launching the beetle at Stritch (only because he likes bugs).
After I got the hookshot, I noticed the chimney of the Knight's Academy had a target that I could grapple onto, so I got in Zelda's bedroom... but I noticed how I could peer into the bath from the air vent. So, my sister regrets suggesting it, but I decided to figure out who was hogging the bath at nighttime... I found Gaepora shirtless in the tub, just chilling there. xDD I tried to make a ruckus in the air vent and see if he would respond to it, but he didn't...
This one is just me being weird, but I took all of the pumpkins from the patch overlooking the lake in Skyloft, and tossed them all into the water.
This was the result. I then enjoyed doing the corkscrew attack, destroying them all. A little irrelevant, but I still tried to do it. ;p