top 3 educational sites for students in india

1.meritnation.com(partially free)

• provides free demo of 1st chapter of every subject.
• provides free ncert Questions/answers.
• some free videos are also there.
• but does not provide videos for every question. 
• it is not free,its notes,explanations,and many more facilitation are not free.
• contains syllabus of ever class from 1-12 and of every board. (you should yourself try it once its registration is free)

2.topper learning .com(partially free)

• its same as merit nation,but its explanatory videos are superb.
• one should go for topper learning if you are confuse in merit nation and topper learning.
• contains syllabus of ever class from 1-12 and of every board.  (you should yourself try it once its registration is free)

3.mydrona.com(totally free)

• videos are superb.
• does not provides notes.
• but explanation is great.
• its my Favorite  , because its free and very useful too.
• you can log in into it through Google and Facebook accounts   
• (this one is the best)mind it!!!!