OCR GCSE Computer Science (J277)Specification point 2.2.3

OCR J277 2.2.3: Additional programming techniques

The free BugBot lessons that teach this point, a robot to try it on, and the past-paper questions that test it.

Lessons that teach it

1. F1.3 Calling functions Programming basics
   Arguments, telling and asking, and notes on the robot's buzzer.
2. F3.1 String handling Strings, lists and records
   Length, indexing, slicing, searching and joining strings, and f-strings.
3. F3.3 Lists: one-dimensional arrays Strings, lists and records
   Making, indexing and changing a list; append, remove, in, split and join.
4. F3.4 Iterating over a list Strings, lists and records
   Loops over items and indexes, totals, counts, min and max, and linear search.
5. F3.5 Two-dimensional arrays Strings, lists and records
   Rows and columns: the depth grid as a list of lists.
6. F3.6 Records Strings, lists and records
   Grouping related fields: a sensor reading as a record, and a list of records as a table.
7. F3.7 Random numbers Strings, lists and records
   randint, choice and seeds: dice, random tunes and a robot that wanders.
8. F4.1 Writing functions Functions and structured code
   def, calling, and why subprograms help.
9. F4.2 Parameters and return values Functions and structured code
   Information in and an answer out; procedures and functions.
10. F4.3 Local and global variables Functions and structured code
    Scope: where a variable exists, and why passing values beats global.
11. F4.5 Libraries and your own modules Functions and structured code
    import, Python's own libraries, and a module file of your own.
12. F7.1 Reading and writing files Files and databases
    Open, read, write, append and close: a run log in a CSV file.
13. F7.2 Relational databases Files and databases
    Tables, records, fields, primary and foreign keys, and avoiding redundancy.
14. F7.3 SQL: SELECT Files and databases
    SELECT, FROM, WHERE and ORDER BY on the class's robot runs.
15. F7.4 SQL: two tables and changing data Files and databases
    Queries across two tables; INSERT, UPDATE and DELETE, and the robot logging its own runs.

Try it on a robot

The task from F1.3 Calling functions, running here. Change the program and press Run.

Past paper questions on this

Real exam questions that test this, each worked through with a program you can run.

• AQA 8525 June 2025 Paper 1, Question 7: Read a subroutine: purpose, outputs, return value, parameter 7 marks
• AQA 8525 June 2025 Paper 1, Question 8: Trace a loop that compares two binary strings with OR, NOT and AND 6 marks
• AQA 8525 June 2025 Paper 1, Question 9: Which of five algorithms correctly total an array 2 marks
• AQA 8525 June 2025 Paper 1, Question 10: Records, and the smallest value in an array without min or sort 8 marks
• AQA 8525 June 2025 Paper 1, Question 11: Trace findLetter, then write the word game that calls it 14 marks
• AQA 8525 June 2024 Paper 1, Question 1: LEN, POSITION, a data type, assignment, and a two line program 6 marks
• AQA 8525 June 2024 Paper 1, Question 3: random.randrange, a test plan, and a syntax and a logic error 6 marks
• AQA 8525 June 2024 Paper 1, Question 7: Build a stock code with string indexing and concatenation 4 marks
• AQA 8525 June 2024 Paper 1, Question 8: Trace a loop over three arrays that uses DIV 6 marks
• AQA 8525 June 2024 Paper 1, Question 9: A data structure, a RECORD definition, and the dearer of two books 7 marks
• AQA 8525 June 2024 Paper 1, Question 10: Trace three subroutines that call each other 2 marks
• AQA 8525 June 2024 Paper 1, Question 12.1 to 12.5: A sliding puzzle: move tiles, and read nested loops that find the blank 7 marks

The specification is OCR's own document; this page says which of our lessons teach point 2.2.3 and is not endorsed by the board.