I need to improve a lot in IIT MATHS. I M preparing for iitjee 2011 and is now in class XI. what should I do in 1 yr. to strengthen my concepts and problem solving abilities in order to crack iit.... please suggest a few steps .. I am not so sure of class XI concepts... should I start of with class 12 or strengthen class 11 topics first.. please suggest a few good books for improving the concepts

Even i am giving entrances in 2011 and have not yet completed the 11th syllabus. But i am going to concentrate about two more months on 11th syllabus because i dont think 11th syllabus should be left behind because many questions in entrances are based on 11th. i am taking online iit lectures for maths and dont o which books could strenghthen the concepts but would advice you to build on the 11th concepts before moving to new topics.