IIT JAM Exam conducted by IIT’s every year. The level of this exam is so high because it is the exam for taking admission in top most colleges of IIT’s or IISc’s.
If you are not preparing in the right direction with right strategy then you will not be able to qualify this exam.
If you are searching for online study material I would suggest you to buy it from Eduncle. It is the one of the best coaching for IIT JAM exam.