Yes, VIT does accept improvement marks for admission.  This applies to both the VIT Engineering Entrance Exam (VITEEE) and your board exams. You can appear for the VITEEE even if you are planning to take improvement exams for your board exams.  VIT will consider your improvement exam scores for admission as long as you meet the minimum eligibility criteria at the time of admission. This typically involves securing at least 60% in Physics, Chemistry, and Mathematics/Biology in your +2/ Intermediate exams.

If you meet the eligibility criteria with your improved marks, you can attend classes at the VIT Vellore campus. There is no separate restriction on attending classes based on whether you took improvement exams or not.

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I hope it helps!