Grade 9: Computing
Start with a unit whose prerequisites fit. Work through the lessons, use the study guide to review, and try the new cases before continuing.
- Unit 1 · 4 lessons
Build a Threat and Recovery Model
Model a private-record endpoint that lacks authorization and a usable backup made at hour 5 before failure at hour 8. Select controls and a data-preserving test.
Before you begin: Explain permission checks and distinguish saved from unsaved work.
- Unit 2 · 4 lessons
Read Text Files and Structured Formats
Interpret CSV A,"red,blue",5 and JSON {"id":"007","count":5}. Plan a read-only source inspection and a separate derived output.
Before you begin: Read text, field schemas and collection literals.
- Unit 3 · 4 lessons
Build Evidence for Small Functions
Test a function’s contract, boundaries and list structure, then retain regression cases.
Before you begin: Read inequalities; use zero-based list positions; trace if/else and accumulators.
- Unit 4 · 4 lessons
Publish a Reproducible Data Argument
For 12 completed attempts out of 15 supplied attempts, write a reproducible result with provenance and a limit. Separately classify an unavailable phone test.
Before you begin: Calculate percentages and explain the scope of a dataset.
Check what you can explain
The subject test uses additional supplied cases across these units. Its feedback links back to the relevant lessons. Use it to plan practice; a score on these questions is not a school grade or proof of complete subject mastery.
Open the subject test