Nagpur: Acknowledging widespread concern among students, including hundreds from Nagpur, over unexpectedly low scores in the CBSE Class 12 board examinations under the On-Screen Marking (OSM) system, the Union education ministry on Sunday said it had identified and rectified minor issues in the evaluation process.Union secretary of school education Sanjay Kumar said around 68,000 answer sheets were rescanned after poor initial digital capture, while nearly 13,000 were later evaluated manually. The board has also initiated the re-evaluation process as part of its standard procedure.Soon after CBSE declared the results, several students alleged that answers and diagrams were overlooked during the digital assessment, resulting in unexpectedly low scores across multiple subjects.CBSE said it had examined the grievances raised by students and acknowledged the anxiety surrounding the results. Under the re-evaluation process, students can obtain scanned copies of their answer books, compare the assessment with the marking scheme available on the CBSE website, and submit objections. A committee of subject experts will review the submissions and communicate its decision.The board reintroduced OSM this year after discontinuing an earlier attempt in 2014 due to technical limitations in scanning. Nearly 98.66 lakh answer books were scanned during the 2026 examination cycle. Of these, 68,018 were rescanned because of poor image quality, while 13,583 with persistent scanning issues were assessed manually.CBSE said extensive preparations preceded the rollout. A dry run was conducted on January 20 and 21 at five schools involving 100 teachers. Demonstrations were later organised for teachers, following which the system was upgraded based on feedback. A webinar held on February 13 was attended by schools and teachers nationwide, with the recording viewed more than four lakh times. The portal for teacher login and practice using previous years' answer books was opened on February 15, while the actual evaluation began on March 7.The board admitted that initial technical problems included delays in whitelisting static IPs at schools, server overload, download failures, and login issues caused by incorrect data submitted by institutions. In some cases, students answered papers in languages different from those recorded in the database, prompting evaluators to temporarily reject those answer books before reassigning them. CBSE said all issues were resolved during the evaluation process. InfoWidespread concern: Stakeholders, including students, guardians and teachers, raised doubts about the OSM marking process.Concerns raised:Poor scanning quality led to teachers assigning marks incorrectlyStrict adherence to stepwise marking penalised students who used shortcuts or methods different from those in the marking schemeMathematics, Physics, and Chemistry identified as the most affected subjectsConcerns also raised about students who scored 95 percentile or above in JEE Mains but received poor marks in board exams.Dip in pass percentage: A statement issued by the education ministry through CBSE officials said both the pass percentage and average marks recorded a slight dip in 2026.Analysis of grade cut-offs showed that in Physics, Chemistry, Mathematics and Accountancy, lower-level thresholds declined by one to three marks compared with previous years, while cut-offs in other subjects remained stable or improved.Officials attributed the trend to strict adherence by evaluators to the marking scheme prepared by subject experts, which emphasises conceptual clarity and rigour over shortcuts. The board added that the scheme also accommodates alternative methods of answering questions, provided they are within the prescribed syllabus.