'520' is an abbreviation of "I love you". Many people, young and old, have their own way to celebrate the date. 500 students in Grade 3 and their teachers in People Primary School in Chongqing Municipality wore pajamas to school to celebrate this past May 20. Some students even gave away Thanksgiving cards and Friendship cards to their classmates while exclaiming "Today is our family day, we are a loving family! ", according to Chongqing Evening Daily.

Visit the original source and full text: Shanghaiist