Introducing, and thereafter teaching calculus to senior secondary, early college and university students, at the expense of algebra and geometry, is causing half-baked calculus being served to relatively under-prepared students. In line with this proposition, the current research aims to identify how cognition of calculus takes place among learners, what teaching methodologies are used by Indian teachers, what pedagogical techniques are most efficient in calculus teaching, and what prerequisites are called for before commencement of the course on calculus? For this extensive study, data was gathered from school teachers and assistant/associate professors of colleges and universities, having more than 6 years of calculus teaching experience, drawn from 26 schools, 19 colleges and 7 university departments, spanning across 23 different states and union territories of India. A total of 142 teachers took part in this study. Data was collected using schedules, classroom observations, focus group interviews, and informal discussions that were carried out both before and after the classroom teaching. NVivo and Concordance softwares were used for analysis of the emerging content and classroom discourses. The study traversing between February 2016 to April 2019, is qualitative in its framework and lies purely within the interpretivist paradigm. The findings of this research shall mellow the understanding of calculus cognition operational among school, college and university going students.