Math kangaroo kangaroo math contest is the largest math contest for teenagers in the world, which is open to students of grade 1- 12. The contest originated from a popular mathematics contest initiated by the famous Australian mathematician Peter O'Halloran in 1980s, and it is 199 1. In order to pay tribute to this Australian mathematician, the contest was officially named Mathematical Kangaroo Kangaroo Mathematical Contest. Different from the difficulty and challenge emphasized by the traditional Mathematical Olympiad, the purpose of Kangaroo Mathematics Competition is to stimulate children's interest and confidence in mathematics learning with interesting and vivid topics close to life. These seemingly simple topics are all unique "thinking gymnastics", which is helpful to train and cultivate students' mathematical thinking. Soon, this incident spread rapidly in Europe. From 65438 to 0998, this competition spread to the United States, and a non-profit charity "American Mathematical Kangaroo" (NFP) was established to organize and promote American competitions. Since its founding 40 years ago, more than 6.3 million students from 87 countries and regions around the world have participated in the competition, which is a math competition suitable for students at all levels.