Primary and secondary schools in Nanjing celebrated the International Day of Mathematics (IDM) on March 14, or Pi Day.

Zu Chongzhi (429-500), a Chinese astronomer and mathematician, was most notable for calculating pi as between 3.1415926 and 3.1415927, a record in accuracy.

Nanjing Guanghua East Street Primary School held a challenge to memorize π to as many digits as students could, first at the class level and then at the school level. Some students were able to correctly recite the mathematical constant to 100 digits.

"I find it challenging and fun," said Qi Hanchen, a third-grader at the school. Qi added that he memorized five digits as a group and reached 200 digits after practicing for three days.

In the view of Zhang Shufang, vice principal of the school, this competition has inspired students to find creative ways for effective memorization, such as in groups and through songs, thus cultivated their interest in mathematics and spirit to take up challenges.

At the Math Festival in Nanjing Foreign Language School Yuhua International Academy, the fourth-grade classes competed in logo design after teachers introduced Pi Day. Students were encouraged to conduct research and feature elements of the school in their entries.

A design by five students from Class 8 won praises from the teachers, as it features a circular border, waves in the shape of π as the main background, the number 3.14, a sailboat, and seagulls to symbolize the uplifting culture.

Wang Kehan, math teacher at the school, said classes of different grades all had programs to mark the International Day of Mathematics, such as finding the shape of circle in life for first-graders, making a bookmark with digits in π for second-graders, and creating abstract drawings with circles for fifth-graders.

(Photo from the Yangtse Evening Post)

At the Gulou Experimental Middle School, students had a cosplay to pay tribute to mathematicians such as Pythagoras, Euclid and Hua Luogeng.

Yan Zimu, a second-year student, said the rehearsal lasted for 20-30 minutes every night and the program helped learn the history and importance of math.