There is not much advantage if you are talking specifically about JEE concepts and topics. We were not made to study that because it would have been too much for us at that age, but yeah there are some serious advantages one can have from starting that early for IIT JEE.
- Time : You learn to respect and manage time very early. By the time you start with JEE preparation (the final 2 years), you are already in that habit of managing things.
- Routine : Going to coaching, coming back home , doing your homework, managing school related things, etc. All this become a part of your routine.
- Foundation : You see, the best buildings created are those ones who have the strongest foundation because it takes a lot of effort and power to make them fall. When you start preparing in class 9th or 10th, you are always a few steps ahead of most of your companions. I remember that we were taught a lot about geometry, algebra, vectors, thermodynamics (very basic) during that time and all that helped in some or the other way in last two years. A lot of complicated things such as Voltage, current rules, Magnetic models, etc were also taught so to make the base very clear from that time only.
- Realisation : I think this is one of the most important and biggest factor why one should start off preparing so early. Its very important to realise that life is not going to be spoon feeding always. If you really want to make a mark, you need to get out of your comfort zone and act accordingly. At such a young age, when most don’t even know full form of IIT (yeah, its true), if you are able to make such a decision then go with it and are able to realise this main thing I am talking about, its just not good for preparation of JEE but for preparation of life as a whole.
I guess this should help you out in taking a decision.
All the best 🙂
Related Page : IIT JEE Foundation