Ah, May the 15th, Teacher's Day. Well, in Mexico and South Korea, for that matter. The day many students go to their teachers to give them a small gift, not knowing that their houses would be chock full of gifts later on. My mother, for example, is a teacher, and always comes home with an amount of candy that would put Halloween to shame.
On October 5th, 1966, there was an intergovernmental conference in UNESCO where they tried to debate about the Status Of Teachers. They adopted the Recommendation that gave teachers their responsibilities and defined their rights. World Teacher's Day is celebrated in over 100 countries, and lays emphasis on the contributions and achievements of teachers throughout the whole world.
So go to your favorite teacher, thank her for everything she's ever taught you, shower her with chocolates and tell her you love her (you know, in a non-creepy way), because you can never, ever repay something as wonderful as the knowledge bestowed upon you.