IB Physics 2025: A Full Two-Year Plan and Core Task Guide

Apr 23, 2026 ·

With the first examination of the restructured 2025 IB Physics syllabus, in which all option modules were removed and the content was reorganized into five major themes, international schools usually distribute the 150 hours required for SL or the 240 hours required for HL across four semesters.

As a teaching and exam-preparation guide, this article maps out the core milestones of the standard two-year programme, from DP1 to DP2, the study focus of each semester, and the key differences between the Physics IA and EE, with the aim of offering a detailed and genuinely usable planning reference.

1. The Full Two-Year Structure

1.1 Core Timeline Across the Two Years

The table below shows the major milestones from the start of DP1 to graduation at the end of DP2. Note in particular that 20 April is the global final deadline for all process-based components such as IA, EE, and TOK.

Stage	Physics coursework	IA (Scientific Investigation)	EE (Extended Essay)	TOK (Theory of Knowledge)	CAS (Core Requirement)
DP1 Semester 1	Foundations of mechanics and thermal physics	Basic experimental skills training	Learn the process and choose a subject area	Introduction to core epistemological ideas	Set up records and begin routine activities
DP1 Semester 2	Waves, circuits, and participation in CSP	Choose a topic in May and set the plan	Begin in January and define the topic	Exhibition topic selection and planning	Plan the CAS Project
DP1 Summer	Independent review and weak-point repair	Complete experimental data collection	Write the first draft and continue deep reading	Strengthen the logic of the Exhibition argument	Carry out the project work
DP2 Semester 1	Field theory and school mock exam 1 in December	Write the first draft and handle error analysis	Submit first draft in September	Formal Exhibition presentation	Continue updating reflection records
DP2 Semester 2	Quantum physics, relativity, and mock exam 2 in March	Submit final version in February or March	Finalize in November	Write and submit the TOK Essay	Complete CAS by mid-April
May of DP2	Final Exam	Official moderation in progress	External marking in progress	External marking in progress	Completion officially confirmed

1.2 A Closer Look at the Major Tasks

Physics coursework and the Collaborative Sciences Project (CSP)

CSP is a compulsory component for IB Group 4 sciences. It emphasizes cross-disciplinary collaboration in solving real-world problems. Although it does not directly contribute to the 45-point total, it is still a required condition for receiving the diploma.
The external assessment (EA) accounts for 80% of the final subject grade. Under the 2025 syllabus, the addition of Paper 1B, which focuses on experimental and data analysis, means students must develop genuinely solid practical reasoning in physics.

Physics IA (Scientific Investigation)

Weighting: 20% of the subject grade.
Practical advice: data collection should be completed in the DP1 summer break. DP2 quickly becomes overloaded with field theory, writing deadlines, and exam preparation, so this is not something students should postpone and redo later.
Assessment: the IA is marked using four equally weighted criteria, each worth 6 marks, for a total of 24. The emphasis is on the rigor of scientific inquiry.

Physics EE (Extended Essay)

Core role: together with TOK, the EE determines the 3 core points. It is an advanced and demanding challenge that usually requires about 40 hours of independent investigation.
Survival advice: do not choose a Physics EE just because it sounds impressive. Unless you have very strong mathematical ability, access to university-level datasets such as public astrophysics catalogues, or the ability to build a complex controlled experiment, it is often wiser to choose a humanities or social science subject in which you are genuinely stronger. At the top level, Physics EE marking places great weight on discussion of where the theoretical model begins to break down, for example through residual analysis.

TOK (Theory of Knowledge)

Core value: TOK is not empty philosophy. It is a serious reflection on how knowledge is produced and validated.
A practical strategy against wasted effort: science students should learn to reduce complexity by drawing on what they already understand well. In an Exhibition or Essay, it is often more effective to use material from the history of physics, such as the shift from Newtonian mechanics to relativity, or examples from one’s own experiments, such as how instrumental uncertainty limits a physical model. Use the logic of physics that you already know instead of exhausting yourself in unfamiliar abstract theory.

CAS (Creativity, Activity, Service)

Veto power: CAS contributes no academic points, but it is still the absolute entry ticket to the diploma. If the system does not show Complete before it closes, even a perfect exam score will not save the diploma.
Practical execution advice: give up grand, idealized social projects that feel meaningful but consume unreasonable amounts of time and energy. The first goal should be survival and efficient conversion. Learn to reuse your physics work in multiple ways, for example by turning a lab idea into a short science video or by helping younger students with physics tutoring at school. Converting academic work directly into Creativity or Service evidence is often the most pragmatic approach.

Practical work in physics

The official requirement is based on hours, not number of experiments. Under the IB Practical Scheme of Work (PSOW), SL students must complete 40 hours of practical work and HL students must complete 60. Within that time, the specific experiments are chosen by the teacher.
This is survival training, not badge collection. The 2025 syllabus introduces Paper 1B (data and experimental analysis). The reason certain foundation experiments are listed in a plan like this is not to complete a checklist, but to build reflexes so that when students see any set of data with uncertainty in an exam, their minds immediately go to maximum and minimum slope lines and error reasoning.

1.3 Scoring Logic: What 7 Points in Physics and 45 Points Overall Really Mean

In the IB system, the first step in avoiding wasted effort is to understand how the scoring actually works. Percentages on their own can be misleading, so it is better to translate them into the final absolute scores.

1. A single-subject view: the 7 points in Physics and the return on effort

Internal Assessment (IA): this is 20% of the final subject grade. In practical terms, it contributes only 1.4 points out of the total 7.
External Assessment (EA / final exam): this is 80% of the grade, which means it contributes the remaining 5.6 points.
A survival rule against wasted effort: many students think that because the IA is submitted in February, it does not clash with exam preparation in May. That is a very dangerous illusion. The real golden period for raising exam performance is precisely the winter break and the period through February in DP2, when students should already be doing serious cross-topic problem practice. If a student spends an extra 50 hours at that point polishing an IA from “already strong” to “visibly perfect,” that is a clear mismatch of effort.
A pragmatic strategy: secure the core IA marks as efficiently as possible by ensuring correct format, solid data processing, and a coherent chain of error analysis. Once the IA is already in a high and stable range, every additional hour spent polishing minor details may be stealing time from the much more important task of pushing the exam score toward a 7. The real battleground is always the final exam paper that carries 5.6 points of absolute weight.

2. A whole-diploma view: the trade-offs inside the 45-point system

Subject points (42 points): these come from six academic subjects, usually three HL and three SL, with each subject worth up to 7 points. So 6 × 7 = 42.
Core points (3 points): these are jointly determined by TOK and the EE. The official matrix converts the grade pair across these two components into 0 to 3 points. If either one receives an E, not only do the core points collapse, but the student also triggers a failing condition and cannot receive the diploma at all, regardless of subject scores.
CAS (the zero-point bottleneck): CAS does not count toward the 45-point total, but it still has the same veto structure. If it is not completed, the diploma is lost.
A practical anti-overinvestment rule: if Physics or another major subject is still unstable at around a 5, it is usually a bad trade to grind the EE in order to chase an extra core point. Raising marks in the 42-point subject base is almost always more efficient and more achievable than squeezing extra value out of the 3-point core block. Protect the core minimum, and keep your ambition focused on the subject exams.

2. A Semester-by-Semester Task Breakdown

Many students have the false impression that IB Physics is simply a matter of completing a few required experiments from the syllabus. That is a deeply misleading way to see the course.

First reality: what matters is the total practical time, not the number of experiments. Under the IB Practical Scheme of Work (PSOW), SL students must complete 40 hours and HL students must complete 60. The actual experiments chosen inside those hours are decided by the teacher.
Second reality: practical work is survival training, not badge collection. With the new Paper 1B (data and experimental analysis) in the 2025 syllabus, the point of the so-called “foundation experiments” is not box-ticking. It is to build reflexes so strong that the moment students see uncertain data in an exam, they instinctively start thinking about maximum and minimum slope lines and uncertainty logic.

2.1 DP1 Semester 1

Core task: build the mathematical and physical foundations for classical mechanics and basic thermal physics.

Main study focus:

Tools: measurement, uncertainty, and vector operations, which remain fundamental throughout the course.
A.1 Kinematics: constant-acceleration motion and projectile motion.
A.2 Forces and momentum: Newton’s laws and conservation of momentum.
A.3 Work, energy and power: conservation of mechanical energy.
B.1 Thermal energy transfers: specific heat capacity and phase change.
B.2 Greenhouse effect: Earth’s energy balance.
Additional Higher Level (AHL): HL students also begin A.4 Rigid body mechanics, including torque and rotational inertia.

Foundation experiments and core skills:

Experiments: measuring gravitational acceleration $g$ and verifying momentum conservation.
Skills: becoming fluent with photogates or ticker timers, and mastering basic uncertainty propagation.

Major tasks and assessments during the semester:

Semester exams: monthly tests and the term final, with special emphasis on the rigor of uncertainty calculations.
CSP: initial exposure to how science collaboration works, while observing possible cross-disciplinary topics.
IA: basic lab-report training and familiarity with standard Physics IA formatting.
EE: attending school briefings and understanding the methodological threshold for a science EE.
TOK: introductory discussion of “the nature of knowledge” and how physical laws are validated.
CAS: activating ManageBac and beginning routine records of Action or Service activities.

2.2 DP1 Semester 2

Core task: complete the study of material properties, enter the foundations of wave physics, and begin the first serious IB core project cycle.

Main study focus:

B.3 Gas laws: the ideal gas equation and kinetic theory.
B.5 Current and circuits: Kirchhoff’s laws.
C.1 Simple harmonic motion (SHM) and C.2 The wave model.
Additional Higher Level (AHL): B.4 Thermodynamics (AHL), including the laws of thermodynamics and entropy, for HL only.

Foundation experiments and core skills:

Experiments: measuring the EMF and internal resistance of a dry cell, and verifying Boyle’s law.
Skills: mastering linearization, and understanding the physical meaning of graph intercepts and slopes rather than treating them mechanically.

Major tasks and assessments during the semester:

CSP (formal launch): around 10 hours of compulsory interdisciplinary experimental work, usually the first real Group 4 core requirement of the DP years.
DP1 end-of-year exams: these usually start to resemble official assessment style and begin shaping the predicted grade.
IA: topic selection in May or June, followed by a pilot study to test feasibility.
EE: launched in January, with supervisor allocation. A Physics EE usually requires locking in a question that goes beyond the standard syllabus.
TOK: beginning the topic and object planning for the Exhibition.
CAS: planning the CAS Project, with clear attention to challenge and collaboration.

2.3 DP2 Semester 1

Core task: tackle abstract field theory and wave phenomena while entering the heavy writing phase for the IA and EE.

Main study focus:

C.3-C.5 Wave phenomena: refraction, interference, and the Doppler effect.
D.1-D.3 Field theory: gravitational, electric, and magnetic fields, and motion in electromagnetic fields.
Additional Higher Level (AHL): HL students must also handle multi-slit diffraction and more advanced treatment of electric potential $V$ and gravitational potential.

Foundation experiments and core skills:

Experiments: equipotential mapping and double-slit interference measurements.
Skills: handling the uncertainty of very small measured quantities, and turning abstract field models into something physically interpretable.

Major tasks and assessments during the semester:

IA: writing the first full draft, using data collected in the summer and carrying out serious error analysis.
EE: first draft due in September, with the final version normally completed later in the term.
TOK: formal completion of the Exhibition and the beginning of TOK Essay planning.
CAS: entering the most activity-intensive phase, with continued reflection updates to ensure that all seven learning outcomes are evidenced.
Mock 1: usually focused on fields and wave phenomena, and often a major indicator of whether a final 7 in Physics remains realistic.

2.4 DP2 Semester 2

Core task: finish the microscopic and modern topics, then move into full exam simulation before the final papers.

Main study focus:

E.1-E.5 Atomic, nuclear, and astrophysical topics: radioactive decay, nuclear fission and fusion, and the Hertzsprung-Russell diagram.
Additional Higher Level (AHL): D.4 Electromagnetic induction, E.2 Quantum physics, and A.5 Special relativity.

Major tasks and assessments during the semester:

IA (final submission): usually in February or March. At that point, the 20% internal component is effectively fixed.
Mock 2: a full simulation of the final exam, often important for predicted grades and late university decisions.
TOK: writing the TOK Essay, with science students often advised to choose a prompt connected to natural science.
CAS: completion by mid-April, including the final interview to ensure the system shows Complete.
Final external exams in May (EA): * Paper 1 (36%): Paper 1A multiple choice plus Paper 1B experimental analysis. * Paper 2 (44%): longer cross-topic “linking” questions.

3. A Detailed Comparison of the Physics IA and EE

3.1 Physics IA (Scientific Investigation)

20% of the subject grade | 24 marks | within 3,000 words

The IA focuses on the rigorous application of syllabus-level knowledge, usually by investigating a quantitative relationship between one independent variable and one dependent variable.

Recommended formats:

Hands-on experiments: usually the strongest option, using standard apparatus such as photogates and sensors.
Database studies: especially suitable for astrophysics, using real data from sources such as NASA or CERN.
Simulations: allowed, but usually much harder to score highly because the Evaluation criterion is weaker without real system error.

Expected structure:

Introduction: a clearly defined research question (RQ), supported by physical background and relevant derivations.
Methodology: an apparatus diagram and a clear explanation of how system error is reduced.
Data Analysis: raw data, processed data, and linear fitting with uncertainty bars.
Conclusion: comparison with accepted values and a clear final result.
Evaluation: deeper discussion of limitations and physically meaningful improvements.

The four 6-mark criteria in practice:

Research design (6): the clarity of the RQ and the repeatability of the method.
Data analysis (6): uncertainty calculations, error bars, and maximum/minimum gradient reasoning.
Conclusion (6): whether the conclusion is genuinely derived from the data and whether it is compared with accepted values.
Evaluation (6): whether the criticism of the design is specific, meaningful, and realistically actionable.

3.2 Physics EE (Extended Essay)

A major source of the 3 core points | up to 4,000 words

The EE goes beyond the syllabus and usually involves a deeper investigation of more complex phenomena, often with multiple interacting variables.

Common routes and strategies:

Science EE in Physics: high workload and very high value, but it demands deeper literature review and a more complex design, and is usually more suitable for students aiming at top science and engineering programmes.
Interdisciplinary WSEE: combining Physics with another field, such as economics, to investigate global issues like energy efficiency or cost analysis.

The depth expected in the structure:

Theoretical Framework: a more advanced literature review, often involving calculus-based reasoning.
Analysis and Discussion: not just routine uncertainty analysis, but also discussion of the limits of the model, often through residual analysis.

The broad 34-mark structure:

Focus and method (6): the academic value of the question and the soundness of the approach.
Knowledge and understanding (6): command of the academic background.
Critical thinking (12): the depth of the analysis and the reliability of the conclusions.
Presentation (4): structure and referencing discipline.
Engagement (6): the quality of the three reflection sessions recorded in the RPPF.

Final Note

For students in DP1, or for those who have only just entered the IB system, the purpose of this guide is not to draw an unrealistically easy blueprint. Its real value is to expose the “system errors” that consume huge amounts of energy if they are not recognized early.

Do not fall into abstract anxiety about the final score. Treat every task listed here as a concrete variable that has to be handled and closed off one by one.

Forget the fantasy of shortcuts. If you hit each milestone on time, work pragmatically, and move step by step, the result will follow.