Internal Assessments (IA) for the International Baccalaureate (IB)

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12 Jul 2025, 00:00 Z

TL;DR
Every IB Diploma subject sets an Internal Assessment worth 20 % of the final grade in Physics, Chemistry, Biology and both Mathematics courses. It is marked on five universal criteria—Personal Engagement, Exploration, Analysis, Evaluation, Communication—totalling 24 marks. Schools must devote ≈ 10 timetabled hours to the work, and successful reports stay within 6-12 pages (≈ 2 500 - 3 000 words). Early scoping, spreadsheet fluency and sound uncertainty budgets are the biggest levers. This post shows IP students when to start, how to pick Physics- and Maths-friendly investigations, and where specialist tuition plugs the LINEST + \(\sigma\) gaps.

1 | What the IA Is —and Why Integrated Programme (IP) students Should Care

Mini-thesis inside the diploma. One individually written investigation per subject, marked by the teacher, then moderated by the IB; 20 % of the course grade for Group 4 Sciences and Group 5 Mathematics.
Tight frame. The IB specifies no fixed word limit, but recommends staying within 6-12 A4 pages or roughly 2 500-3 000 words so that moderators can read them efficiently.
≈ 10 classroom hours. Guides for Physics, Chemistry, Biology and Mathematics allocate 10 “dedicated class hours” to planning, execution and write-up.
Skill overlap with IP Weighted Assessments (WAs). Planning, LINEST gradients, ± SE quoting and ACE-style evaluation mirror the A-Level H2 Paper 4 rubric your Y5-6 IP students will meet.
University hook. Selective STEM degrees (e.g. Cambridge Natural Sciences, Imperial Engineering) invite IA/EE titles in supplementary questionnaires, so a Math-Physics crossover project signals depth early.

2 | Mark-Scheme Anatomy (Physics / Maths 2025)

Criterion	Marks	% of 24	What examiners look for	STEM example
Personal Engagement (PE)	2	8	Initiative, curiosity, justification of choices	“Why do identical ball bearings damp differently in corn- vs olive-oil?”
Exploration (E)	6	25	Focused RQ, relevant theory, controlled variables, safety & ethics	Pendulum period vs effective length; laser-safety note
Analysis (A)	6	25	Correct processing, uncertainties, appropriate models, `R²`	Spreadsheet `=LINEST()` → \(g = 9.83 \pm 0.06 \space \pu{m.s-2}\)
Evaluation (EV)	6	25	Valid conclusions, limitations, improvements, extensions	Compare phone timer \(\pu{\pm 0.10 s}\) to photogate \(\pu{\pm 0.001 s}\)
Communication (C)	4	17	Logical structure, ≤ 12 pages, APA/MLA citations, labelled figs	Numbered equations, captioned graphs, word-count table

Mark grid confirmed in the official IB Physics and Mathematics AA/AI Guides, first assessment 2025.

3 | Timeline—Synced to IP & MOE Windows

IB Month (DP Y5-6)	Typical MOE / IP Calendar	Key IA Milestone	Tuition Boost
Aug (Y5 T1)	Sec 4 post-promo lull	Brainstorm 3 short-listed RQs; feasibility & risk audit	15 min topic-fit call
Sep-Oct	Sec 4 prelim season	Pilot trials, check variable range & data spread	3 h lab clinic for sensor or spreadsheet setup
Nov (start of 7-wk break)	IP holiday window	Full data collection + on-the-spot uncertainty notes	LINEST + σ crash course
Dec	same holiday	Draft #1 (≈ 2 800 w) → peer & tutor feedback	24 h WhatsApp screencast replies
Jan (Y6 T2)	JC 1 block tests	Revise Analysis & Evaluation; trim to 6-12 pages	Mock moderation with 24-mark rubric
Feb	JC 1 CCA peak	Final proof-read, academic-integrity check, IBIS upload	30 min viva-style Q&A practice

4 | Maths & Physics Topic-Hacks

4.1 Physics SL/HL

Core theme	Data-rich twist	Why moderators smile
Damped SHM	Test three edible oils at 15 °C, 25 °C, 35 °C	Natural log plots → straight-line analysis
Diffraction	3D-printed slits \(\pu{0.05-0.3 mm}\) + phone lux meter	Error sources obvious; safety discussion easy
EMF & internal R	Raspberry-Pi logger at 5 Hz	Yields ≥ 50 points → LINEST precision

4.2 Mathematics AA / AI

Theme	STEM crossover
Logistic model of CCA recruitment	Mirrors enzyme kinetics in Biology IA
Fourier decomposition of ukulele notes	Links to standing-wave Physics IA
Monte-Carlo estimate of irregular pond area	Easy primary-data collection; CAS coding bonus

5 | Common Pitfalls—and Rapid Fixes

Pitfall	Marks at risk	Fix
Exceeds 12 pages with long literature review	C criterion (-1 or -2)	Move background to succinct bulleted appendix
Single trial per IV level	A & EV capped	5-level IV x 3 repeats → 15 data points minimum
Prints Excel with default gridlines	C -1	Export graphs as PNG; remove grid; add axis units
Confuses % error and % uncertainty	EV -2	Always compare: \|%error\| ≤ %unc ⇒ result plausible

6 | How Specialist Tuition Bridges the Gap

Topic-Fit Call (15 min). Map RQ ↔ syllabus ↔ available apparatus.
Holiday Lab Intensives. Hands-on with Vernier sensors, smartphone photogates, Google-Sheets macros.
24 h Screencast Feedback. Send a graph; get an annotated video back inside a day.
Mock Moderation. Tutors grade against the 24-mark grid; students patch before IBIS upload.