To start with go for NCERT textbooks and previous year question papers. They serve quite a lot sufficient base for the NTSE exam. You can also refer to the link for Best Books for NTSE to know about more options for books available for study.
For first stage of NTSE of maharastra state you should not mug up all the things. You shohld go for the NCERT tect book first and if you have covered these text books then you should go for MC graw hill books for competition practise and also go for the mock test available in book that may helps you to get a high score and improve your accuracy level with in time limit .
Hope it helps.
Thank you :)
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