St. Patrick's Day is next Monday. You can learn more about this Christian saint here. We especially lovethis children's book by Tomie dePaloa. It tells the story of St. Patrick and then also about several legends and stories that surround him.
One story that I especially love is how St. Patrick used a shamrock to teach people about the Holy Trinity. One day, while he was teaching, the people were having a hard time understanding how the Trinity worked/functioned/existed. Patrick looked down at his feet and saw a shamrock. He plucked it up and explained that the Trinity is like the shamrock: each leaf represents one part--father, son and holy spirit--but they all share one stem are and are one being.