Need Advice

Currently in class 11 about to move in class 12, I am a above mediocre and below topper student and recently my institute has allloted star batches of which I couldnt be a part of, is it possible to get into a good IIT without being a part of star batch, my class 11 has not been wasted and I feel I could have just put in more hours for question and answers, backlogs in only about three chapters of class 11, please advice regarding this because my institute faculty is very demeaning to the non toppers, often not taking doubts and inputs in a positive manner, my class 11 is not wasted and I am an above average just slightly below topper student. Please advice current peers at IIT Bombay.