Here are my favorite stories from Tibetan Folktales unit:
The Ingratitude of Man. This is also a great story! I really liked the sense of surprise, where help came from where the man least expected it (crow, rat, snake), while he was betrayed by his fellow human. The transformation of the snake was also really cool: the snake turned himself into a ghost and went to choke the king, so the king had to call the lamas to try to figure out what was happening.
The Wise Carpenter. This is a hilarious story about a painter who tries to trick the king into killing the carpenter, but the carpenter turns the painter's trick against him instead. It's a very elaborate trick involving an "ascent to heaven" - the carpenter only pretends to go to heaven, and instead is just hiding in his house for a few months. The painter, however, really believes the carpenter went to heaven and tries the same thing himself... and he really does go to heaven - that is, he dies! It sounds gruesome but it's actually really funny. A great example of trickster tricked.
The Story of Drashup and the Goddesses. Oh, this is such a great story about about how you cannot escape fate. Drashup accidentally learns of his fate from a goddess (he will marry a young bride and that bride will die young). Drashup tries in every way to escape his fate - he even tries to kill the baby who will be his bride! - but there is no escaping fate. I really like the way that the scar from his attack on the woman when she is a baby is what allows Drashup to recognize her later on! And I guess the lesson is that you really don't want to know what your fate is because the whole idea is you cannot do anything about it... no matter how hard you try.