That Blue Square Thing

Syllabus content:
PDF iconUnit 1 content - PDF document to download and print
Note: this syllabus content is a slightly amended version of the one published freely on the web by AQA. I have made very minor adjustments to remove some content less suitable for students to use and it is presented here simply to allow the children I teach to download a usable copy of the syllabus content. It is copyright AQA and reproduced here simply to make access easier for students. No attempt to claim copyright is being made, although I could have copied the text into my own interpretation...

AQA Computer Science GCSE

May 2019: this area of the site is being built just now. I’m making progress but there are areas where there is no content yet. That will get added over the next 6 months or so.


Algorithms show exactly how a task can be completed. Technically they are a sequence of step by step, unambiguous instructions for solving a particular problem.

You need to be able to read (and understand) and write algorithms written in:

In an exam you may have to write an algorithm as well as read one. There is no need for you to be able to write perfect pseudocode - you can use any form of basic English or even programming code. The key is getting the logic right, not necessarily writing with perfect syntax. So, it's important to know what pseudo code commands mean, but it's not essential to write perfect pseudo code.

Key Definitions and Ideas

The key definitions here are really important. Look at the syllabus document. If a word is included in there you must be able to define it.

PDF iconAlgorithm basics - key definitions and ideas

PDF iconBasic flowchart symbols - you might see a flowchart in an exam so you need to make sure you know what each symbole means

There are some key programming ideas that you can use algorithms to help develop.

PDF iconAlgorithm Programming Constructs - an important set of key programming concepts and constructs and how they are developed in algorithms. You should have implemented all of these ideas using Python, but it's important to understand that they are key ideas in programming and know how they can be applied in non-program code algorithms. (Note: some of the pseudocode in this document is not AQA pseudocode - I might get round to updating it at some point, but the ideas are the important thing)

The Bitesize pages on algorithms and control flowwiki link are also useful - especially when you need to review sequence, selection and repetition. There are videos which might be helpful.

Exam style questions

PDF iconDecomposition question - exam style question

PDF iconAdvantages and Disadvantages of using Decomposition - use this to help answer the last question (the 6 mark one)