Joseph Li always says that he is one of the luckiest persons in the world because he chose the thing he is most interested in and good at as his career – mathematics education. This passion and focus also makes him become the best math competition coach in China and the deputy leader of China IMO team (International Mathematics Olympiad). As a student, he won a lot of awards in math competitions, including 2nd place in China Mathematics Olympiad when he was only a 10th grade student. But after becoming a teacher, he helps his students to win even more and more brilliant achievements. During the twelve years that he taught math in Beijing, his students won 7 gold medals and 1 silver medal in IMO. Mr. Li is also one of the pioneers of teaching reform in China: he attaches importance to stimulate students’ curiosity, to help them comprehend the mathematical ideas through challenging projects and discussions, to reveal the beauty of math and power of mathematical thinking with vivid examples. Therefore he won 1st place in the national teaching competitions of high school teachers, and was invited to US to discuss the plan of American mathematics curriculum as the only representative of high school teachers. Now Mr. Li and his colleagues believe that math learning in PRISMS will be interesting and be of high quality.