Free Computer Science Help
Intro computer science is the course where watching lectures feels most productive and does least. Nobody has ever learned to program by watching.
Why computer science grades actually slip
Programming is a performance skill, and the gap between following working code and producing it from a blank file is enormous. Students who revise by reading solutions walk into a practical exam and discover they cannot start. The only study method that works is writing code from scratch, failing, and fixing it — which is uncomfortable, which is why it gets avoided.
The second grade-killer is specific to CS and unusually brutal: deadlines. Programming assignments carry heavy weight and late policies are often severe, so a student who understands the material perfectly can fail on submission timing. Starting the day a problem set is released is worth more marks than any amount of cleverness.
Third, debugging is the actual job and is almost never taught. Students treat an error message as a verdict rather than information. Learning to read a stack trace properly is probably the highest-return hour in the course.
Free resources worth your time
Everything below is free to use without payment. The note on each one says when to reach for it, because the usual problem is not a shortage of material — it is picking the wrong kind of material for the stage you are at.
- Harvard CS50x — Introduction to Computer Science Free course Free, complete, famously well taught, with automatically graded problem sets. The single best free CS course available.
- MIT OpenCourseWare — 6.0001 Intro to CS and Programming in Python Free course Closer to a typical university intro course than CS50. Good if your course is Python-based.
- freeCodeCamp Practice Thousands of hours of practice in the browser. Use it for volume once you know the concepts.
- Khan Academy — Computer Programming Free course Gentler starting point if you have never written code before and CS50 is overwhelming.
What to do with the time you actually have
If you have the rest of the term
Write code every day, even badly, even briefly. Start every assignment the day it is released — not to finish it, just to find out what it will require. The discovery is the point.
If you have a week
Re-implement past assignments from a blank file without looking. If you cannot, you did not learn them the first time; you watched them get solved.
If you have tonight
Practise the exam's specific format. A handwritten code exam, a practical, and a multiple-choice paper need three different kinds of preparation, and people regularly prepare for the wrong one.
Work out what you actually need first
Before you spend a weekend on this, get the number. If the final is worth 20% and you are sitting at 88%, an A needs 98% and a B needs 48% — those two facts call for completely different weeks. Run your real numbers through the final grade calculator, then come back and pick the plan that matches the gap. The finals-week triage guide covers how to split time across several courses at once.