P.K. Srinivasan (PKS) (4 November 1924 – 20 June 2005) was a well known mathematics teacher in India. He taught mathematics at the Muthialpet High School in Chennai, India until his retirement. His singular dedication to education of mathematics would bring him to the United States, where he worked for a year, and then to Nigeria, where he would work for six years. He is known in India for his dedication to teaching mathematics and in creating pioneering awareness of the Indian mathematician Ramanujan. He has authored several books in English, Telugu and Tamil that introduce mathematics to children in novel and interesting ways. He was also a prominent reviewer of math books in the weekly Book Review column of the Indian newspaper The Hindu in Chennai. Experience PKS, as he was known to the world-at-large, among his colleagues, students and friends, travelled to the United States as a Fulbright exchange teacher and worked in Liverpool Central School, New York, in 1965-'66. Later he served as a Senior education officer and a Senior lecturer in Mathematics in Nigeria for seven years. He served as a lecturer in the National Council of Educational Research and Training (NCERT) in India. He organized over sixty math expositions and fairs in India, Nigeria and the United States, and participated actively in four International Congress on Mathematical Education (ICME) conferences. He inspired many a creative idea and gave them shape through demonstrative displays by his students. Conduct of Bharat Dharshan, World Exhibition, three-day three-tier Math Expositions to make all his math students walk across the curriculum which was highly talked about in his days and research papers on subjects from English to Social Studies by students studying from 7 to 12 Standards was an everlasting contribution made by him to the students and to The Muthialpet High School, Chennai where he was a teacher par excellence. He could pick the brightest of students and discuss esoteric topics such as Boolean algebra, Ramanujan's theorems and at same time deploy easy-to-understand teaching tools for teaching mathematics and English. As a class teacher, he could reach across to the poorest performers and made them cross average levels in English and mathematics. Although he hailed from a traditional family, he was always clad in a white kurta and dhoti spun out of khadi - rough and homespun cotton cloth that symbolized the Swadeshi concept of Gandhiji. He sported a