IB Diploma Programme (DP) – Group 4: Sciences

Complete Guide to Subjects, Assessment, Skills & Preparation Strategy. Group 4 subjects in the IB Diploma Programme (DP) focus on understanding the natural world through scientific inquiry, experimentation, data analysis, and evaluation.

Students learn not only scientific content, but also how scientists think, test hypotheses, evaluate evidence, and communicate conclusions.

Group 4 is offered by the International Baccalaureate and is a cornerstone of STEM and science-based university pathways.

What Is IB DP Group 4?
  • Scientific inquiry
  • Experimental design
  • Data collection & analysis
  • Evaluation & reflection
  • Ethical and societal implications of science

Most students choose one Group 4 subject, though many take two sciences (instead of Group 6) for STEM-heavy pathways.

Group 4 Subject Options
Subject Focus Best Suited For
Biology Living systems, life processes Medicine, biology, life sciences
Chemistry Matter, reactions, structure Chemistry, engineering, medicine
Physics Laws of nature, energy, motion Engineering, physics, mathematics
Environmental Systems & Societies (ESS) Human–environment systems Environmental studies, sustainability
Computer Science Computational thinking, programming CS, IT, data science
Sports, Exercise & Health Science (SEHS) Physiology, biomechanics Sports science, physiotherapy

Note: All subjects are available at SL & HL except ESS (SL only in most schools).

Assessment Structure (Group 4 – SL & HL)

Group 4 assessment combines external written examinations with internal scientific investigation.

External Assessment (≈75–80%)
Component SL HL Focus
Paper 1 ✔ ✔ Multiple-choice (breadth of syllabus)
Paper 2 ✔ ✔ Structured & extended response
Paper 3 ❌ ✔ Data-based + option topic questions
Internal Assessment (≈20–25%)
  • One individual scientific investigation (IA)
  • Internally assessed and externally moderated
Core Scientific Skills IB Assesses
  • Knowledge & understanding of scientific concepts
  • Application of science to unfamiliar situations
  • Experimental design & inquiry
  • Data processing & analysis
  • Evaluation of methods & limitations
  • Scientific communication & terminology
Subject-Wise Assessment Focus & Preparation
Biology
Focus Area Details
What Biology Assesses
  • Structure & function
  • Systems & processes
  • Interactions from molecular to ecosystem level
Assessment Highlights
  • Data interpretation
  • Extended explanations
  • Application of biological principles
Preparation Strategy
  • Learn diagrams & processes thoroughly
  • Practise data-based questions
  • Link structure to function
  • Use real biological examples
Chemistry
Focus Area Details
What Chemistry Assesses
  • Chemical structure & bonding
  • Stoichiometry
  • Energetics & kinetics
  • Organic chemistry
Assessment Highlights
  • Calculations with explanation
  • Mechanisms & reactions
  • Practical lab skills
Preparation Strategy
  • Master mole calculations
  • Practise drawing mechanisms
  • Show clear working steps
  • Use correct chemical notation
Physics
Focus Area Details
What Physics Assesses
  • Laws of motion & energy
  • Fields, waves & electricity
  • Mathematical modelling
Assessment Highlights
  • Problem-solving
  • Data analysis
  • Mathematical reasoning
Preparation Strategy
  • Learn definitions & derivations
  • Practise multi-step calculations
  • Master formula manipulation
  • Use units consistently
Environmental Systems & Societies (ESS)
Focus Area Details
What ESS Assesses
  • Environmental systems
  • Sustainability challenges
  • Human impacts & management
Assessment Highlights
  • Interdisciplinary thinking
  • Case-study evaluation
  • Data interpretation
Preparation Strategy
  • Understand system diagrams
  • Learn real-world case studies
  • Practise evaluation language
  • Connect science with society
Computer Science
Focus Area Details
What Computer Science Assesses
  • Computational thinking
  • Algorithms & data structures
  • Programming logic
  • System design
Assessment Highlights
  • Pseudocode & trace tables
  • Algorithm analysis
  • Scenario-based problems
Preparation Strategy
  • Practise pseudocode regularly
  • Learn algorithm logic, not syntax only
  • Trace code step-by-step
  • Use clear commenting
Sports, Exercise & Health Science (SEHS)
Focus Area Details
What SEHS Assesses
  • Human anatomy & physiology
  • Biomechanics
  • Training principles
Assessment Highlights
  • Data-based analysis
  • Application to sport scenarios
Preparation Strategy
  • Memorise key physiological processes
  • Practise interpreting graphs
  • Apply theory to sport examples
Internal Assessment (IA) – Group 4

What the IA Is

  • One individual scientific investigation
  • Approximately 2,000–2,500 words

What IB Looks For

  • Clear research question
  • Appropriate methodology
  • Data collection & processing
  • Evaluation of reliability & validity
  • Scientific reasoning & communication

High-Scoring IA Characteristics

  • Personal engagement
  • Justified methodology
  • Clear graphs & tables
  • Thoughtful evaluation of errors
IA Timeline
Stage When
Topic selection Early DP Year 1
Experiment & data collection Mid DP Year 1
Draft analysis End DP Year 1
Final submission Early DP Year 2
SL vs HL – Key Differences
Aspect SL HL
Content depth Moderate Extensive
Exam papers Paper 1 & 2 Paper 1, 2 & 3
Practical demand High Very high
University preference Accepted Often preferred for STEM
Two-Year Preparation Timeline
Stage Focus
DP Year 1 Build core conceptual understanding, practise data-based questions, begin IA planning early, strengthen laboratory skills
DP Year 2 Finalise IA, practise past papers intensively, focus on exam technique, refine explanations & evaluation
Skills Group 4 Builds (University Readiness)
Skill Where It’s Developed
Scientific inquiry Internal Assessment (IA) and laboratory work
Data literacy Papers 2 & 3 data-based and analytical questions
Evaluation Extended response questions and IA reflection
Scientific writing Internal Assessment and structured exam responses
Problem-solving Application questions across SL & HL exams
How Parents Can Support
  • Encourage curiosity and questioning
  • Support IA planning (not experimentation)
  • Help manage laboratory deadlines
  • Encourage balanced revision
  • Focus on understanding, not rote learning