I started my JEE preparation in 11th std. As per competition, it was bit late, as some students starts from 9th. Maths is most challenging subject when it comes to competitive. Along with some reference book, the best material which helped me to excel in JEE MAIN & JEE ADVANCED was Amit sir's perfect classroom notes.
After completing lectures, I was asking doubts on regular basis which were solved by sir himself. The journey of preparation in MATHS was enjoyable as I had deep understanding of every topic. Thank you sir for teaching, mentoring me in most precious career deciding years.