CBSE Class XII Computer Science Marking Scheme 2026–27 (Code 083)

The CBSE Class XII Computer Science Marking Scheme 2026–27 (Subject Code 083) provides the official answers and detailed evaluation guidelines for the Sample Question Paper for the Academic Session 2026–27.

The marking scheme corresponds to a question paper of 3 hours carrying a maximum of 70 marks. It covers 37 questions, divided into five sections: A, B, C, D and E. All questions are compulsory, with internal choices available in selected questions. :contentReference[oaicite:1]{index=1}

Section-wise Mark Distribution

• Section A: 21 questions × 1 mark = 21 marks
• Section B: 7 questions × 2 marks = 14 marks
• Section C: 3 questions × 3 marks = 9 marks
• Section D: 4 questions × 4 marks = 16 marks
• Section E: 2 questions × 5 marks = 10 marks

The marking scheme confirms that all programming questions are to be answered using Python Language only. :contentReference[oaicite:2]{index=2}

Section A – Objective and Short Answer Questions

Section A provides the correct answers for Questions 1 to 21. It includes questions covering Python lists and strings, tuples, dictionaries, SQL, database concepts, networking, data types, output prediction and assertion-reason questions. Each question carries 1 mark, with the marking scheme generally awarding the mark for the correct answer.

Section B – Conceptual and Programming Questions

Section B contains Questions 22 to 28, with 2 marks assigned to each question. The marking scheme provides detailed evaluation points for concepts such as global and local variables, tell() and seek(), correcting Python programs, user-defined functions, string/list processing, output prediction, SQL commands and computer networking concepts.

Marks are allocated according to individual components of an answer. For example, Question 23 awards 1/2 mark for each of the four corrections, while programming questions may award separate marks for the function definition, logic and output statement. :contentReference[oaicite:3]{index=3}

Section C – Programming and Data Structure Applications

Section C consists of Questions 29 to 31, carrying 3 marks each. The marking scheme provides solutions and component-wise marking for Python file handling, searching/counting words in text files, stack operations and function-based programming.

Question 30 specifically assesses stack implementation, including pushing eligible book records into a stack and popping records. Question 31 evaluates Python functions involving calculations and processing of tuples. :contentReference[oaicite:4]{index=4}

Section D – SQL, CSV and Database Connectivity

Section D contains Questions 32 to 35, carrying 4 marks each. The marking scheme provides individual marks for SQL queries, query outputs, CSV file operations and Python-MySQL database connectivity.

• SQL: GROUP BY, HAVING, DISTINCT, LIKE, ORDER BY, UPDATE and JOIN queries.
• CSV File Handling: Adding rental records and calculating total rental income using Python's csv module.
• Database Operations: Updating records and retrieving data from related tables.
• Python-MySQL Connectivity: Establishing a database connection, creating a cursor, executing an UPDATE query, committing changes and closing the connection.

The marking scheme awards marks for individual programming components such as taking input, opening files in the appropriate mode, creating reader or writer objects, executing SQL queries and correctly committing database transactions. :contentReference[oaicite:5]{index=5}

Section E – Long Answer and Case-Based Questions

Section E contains Questions 36 and 37, carrying 5 marks each. Question 36 assesses binary file handling using the pickle module. Students are required to add enrollment records to a binary file and update the fees of students enrolled in Data Science. The marking scheme distributes marks across function definition, file operations, input, pickle.dump(), pickle.load(), looping, exception handling and updating records. :contentReference[oaicite:6]{index=6}

Question 37 is a computer networking case study. The marking scheme assesses the selection of the appropriate location for a server, network topology, placement of repeaters and switches, transmission medium and VoIP-related knowledge.

The case-based answer identifies the HR Centre for server placement because it has the maximum number of computers and recommends Star Topology. Repeaters are required between the HR Centre and blocks where the distance exceeds 100 metres, while switches are required in each block. Optical Fibre is identified as the appropriate transmission medium, and VoIP (Voice over Internet Protocol) is given as the communication technology. :contentReference[oaicite:7]{index=7}

Evaluation Approach

The marking scheme demonstrates a component-wise evaluation approach. Marks are assigned for specific elements of an answer, including correct logic, appropriate syntax, function definitions, intermediate steps, SQL queries, file operations and database commands. This provides clear guidance for consistent and objective evaluation.

The document also clarifies that there is no change in the Question Paper Design and Assessment Pattern for Academic Session 2026–27. :contentReference[oaicite:8]{index=8}

This Marking Scheme should be used along with the corresponding Sample Question Paper to understand the expected answers, allocation of marks and evaluation methodology for CBSE Class XII Computer Science for the Academic Session 2026–27.