Concepts in computer science
Connect computer fundamentals, networks, databases, and machine learning to system behaviour, limitations, security, and ethical consequences.
Use this IB Computer Science (CS) SL study guide to browse the syllabus topic structure, study materials, and practice resources.
IB Computer Science (CS) SL Question Bank
Jump straight into grouped unit practice without losing your place in the syllabus overview.
Course overview
The current IB Computer Science SL course, first assessed in May 2027, combines Theme A—computer fundamentals, networks, databases, and machine learning—with Theme B—computational thinking, programming, and object-oriented programming. SL focuses on secure application of the shared themes. Paper 2 programming questions are available in Java and Python. The StudyIB topic catalogue below currently retains resources organised under the legacy course whose final assessment is in 2026; use those resources for transferable concepts while mapping revision to the new Theme A/B guide.
Connect computer fundamentals, networks, databases, and machine learning to system behaviour, limitations, security, and ethical consequences.
Specify success criteria, decompose and abstract a problem, construct an algorithm, implement it, and evaluate the result against the original need.
Practise reading, tracing, testing, and writing programs in Java or Python, including object-oriented programming.
For the IB Computer Science SL course first assessed in May 2027, written external assessment and the computational solution make up the final grade. Programming questions on Paper 2 provide Java and Python versions. Confirm your examination session and course language with your school.
| Component | Format | Weighting |
|---|---|---|
| Paper 1 | 1 hour 15 minutes; Theme A concepts of computer science and the case study | 35% |
| Paper 2 | 1 hour 15 minutes; Theme B computational thinking, programming, and OOP; Java or Python | 35% |
| Internal assessment | 35 hours; computational solution to a chosen real-world problem | 30% |
Sources: official IB Computer Science subject brief (first assessment 2027) and official IB Computer Science curriculum update.
Start by identifying the input, output, constraints, success criteria, and required level of abstraction. Trace state changes carefully, use precise terminology, and explain why a solution meets the problem rather than presenting code without evaluation. On case-study questions, apply technical knowledge to the stated context instead of giving a generic answer.
Practise IB Computer Science (CS) SL questionsThe current IB Computer Science course began teaching in August 2025 and is first assessed in May 2027. The previous course has its final assessment in 2026, so students should not treat the two syllabus structures as interchangeable.
SL covers Theme A—computer fundamentals, networks, databases, and machine learning—and Theme B—computational thinking, programming, and object-oriented programming. It also includes a case study, computational solution, and collaborative sciences project.
SL Paper 1 lasts one hour 15 minutes and contributes 35%; Paper 2 lasts one hour 15 minutes and contributes 35%; the computational solution internal assessment contributes 30%.
For programming questions on Paper 2, the course first assessed in 2027 provides equivalent Java and Python versions. Students answer using the language they studied.
The current StudyIB topic catalogue still includes resources organised under the legacy course whose final assessment is in 2026. Many underlying concepts remain useful, but 2027 candidates should map them to the new Theme A and Theme B syllabus and confirm coverage with the official guide and their school.