Digital versus paper route checking

This module is about checking your route before you revise it. Computer Science pages, videos and past questions come from different codes, exam years and notations. A few minutes of checking at the start stops weeks of revising the wrong thing.

Nothing here replaces the Cambridge subject pages. They carry the current syllabus documents and notices, and they win over this site, a textbook or a video. Our Computer Science learning guide shows where this module sits among the others.

What should you already know?

You should be able to read a short loop in pseudocode and follow it with a trace table. If that is shaky, start with pseudocode for the applicable syllabus. If you also write Python, Python transition and execution covers how the same ideas look in code.

An orienting example

Here is one small algorithm. The idea is the same whichever route you follow. Only the way it is written, and where you will be asked about it, depends on your entry.

Total ← 0
FOR Count ← 1 TO 4
   Total ← Total + Count * 2
NEXT Count
OUTPUT Total

Trace it: Count = 1 gives Total = 2. Count = 2 gives 6.

Count = 3 gives 12, and Count = 4 gives 20. The output is 20. Check: 2 + 4 + 6 + 8 = 20.

The same idea in Python:

total = 0
for count in range(1, 5):
    total = total + count * 2
print(total)

The output is again 20. Python’s range(1, 5) stops before 5, so it covers 1, 2, 3 and 4.

Your route check answers one question: which of these two forms will your papers use, and where will you sit them? You cannot answer that from the example. You answer it from your entry and the Cambridge page.

In what order should you work through this module?

1. Identify the entry code: the code and exam year on your entry decide everything else.
2. Why a screen-based route is not a home exam: this removes a common misunderstanding before it affects your plans.
3. Check local centre availability: your own centre, not us, answers what is offered to you.
4. Link a concept to the correct profile: the same idea can be written differently depending on the route.
5. Treat future 0265 availability as source-gated: learn what to do with rumours and announcements.
6. Finish with the mixed practice set.

The pseudocode trace trainer and the Python reasoning sandbox let you practise the example above on short original exercises. They are practice aids, not exam arrangements.

What are the common traps?

• Trusting a subject name. “IGCSE Computer Science” on a video does not say which code or year it was made for.
• Mixing up Computer Science and ICT. They are separate subjects.
• Assuming a screen means home. Where an exam is held is arranged by your centre, not by you.
• Copying a friend’s route. A friend at another school may have a different entry.
• Believing unconfirmed announcements. Check the Cambridge page and date what you saw.

How should you use the practice set?

Do the mixed practice after the five lessons. It mixes route-checking decisions with short traces. Log each slip in the mistake log with the lesson that fixes it.

If you want a teacher to go through your own notes against your entry, our online one-to-one Computer Science tuition starts with a paid one-hour trial.