Answer - No, It is not necessary to appear in JEE (Main) twice. This would be optional for the candidate to appear once or twice for the current academic session. In case a candidate appears in both the tests, the better of the two scores will be used for the admissions and eligibility for JEE (Advance)-2019 they have attempted both the examinations, best of the scores would be taken for the merit list.
Answer - To gauge a student’s potential many exams are conducted at national and state levels. The notable exams are: NTSE - This exam identifies talented students and nurtures them. Scholarships are also awarded to the qualifiers.
KVPY - The Kishore Vaigyanik Protsahan Yojana (KVPY) entrance exam searches for the scientific temper among young students.
Mathematics and Science Olympiads - These gauges a student’s performance in Mathematics and Science at an all India level.
JSTS - The Junior Science Talent Search Examination (JSTS) is conducted separately in each state (union territories too) of India by the respective state education departments only through schools, not individually.
These exams are symbolic of merit and achievement and every student must try to qualify in these.