IB Biology tutor support, built on the course the IB actually examines

In the May 2026 session, 33,585 candidates sat IB Biology HL for a mean grade of 4.5, and 7.4% were awarded a 7. Physics HL, the same session, returned 5.0 and 20.5%. Whatever else IB Biology is, it is not the soft option among the sciences. This page sets out what the International Baccalaureate publishes about the course, and where tutoring actually moves a grade.

Which IB Biology course is your child actually sitting?

There are two IB Biology courses in circulation and only one of them is examined. The International Baccalaureate published a new Biology guide for first assessment in 2025, and it did not tinker at the edges. The third examination paper was deleted along with the Options topics it examined. The internal assessment was replaced by a different task, marked out of a different total, against a different set of criteria. The teaching hours were re-cut. If a student is revising from a book, a video series or a tutor's handout written for the previous course, a real share of that effort is aimed at an examination that will not be set.

The size of the removal is easy to underestimate. In the previous Higher Level course, Paper 3 ran for 1.25 hours and carried 24% of the final grade — close to a quarter of the subject, sat on an optional topic chosen by the school. That paper is gone, and nothing was bolted on to replace it. What happened instead was a redistribution: the current outline puts 36% on Paper 1, 44% on Paper 2 and 20% on the internal assessment, and 36 + 44 + 20 = 100. The two surviving papers simply carry more weight than their predecessors did.

The teaching time did not shrink to match. The guide keeps the recommended figures at 150 hours for Standard Level and 240 hours for Higher Level, the same totals stated in the IB's general regulations. So a course that used to spread across three papers and an Options topic now spreads across two papers and a piece of independent research, with the same hours behind it. In practice that means more depth per assessed component, and it is the main reason advice written for the old course misfires. The content is largely still there. The places where marks are won have moved.

This matters more for the Diploma than for most UK qualifications, because the cohort is small and the resource base is thin. A student sitting A-level biology has decades of past papers, board-published examiner reports and a large market of specialist teachers who have marked the current specification. A Biology candidate on the current IB guide has a handful of live sessions, the IB's specimen material, and a much smaller pool of adults who have taken a class through the new internal assessment and out the other side through moderation.

What does the IB Biology assessment outline actually say?

Below is the assessment outline for both levels, taken from the guide and cross-checked against the covers of the IB's own specimen papers. Read the two columns against each other, because the weightings are identical at Standard and Higher Level while the volume behind them is not. Paper 1 is 36% at both levels, but it is 55 marks in 1 hour 30 minutes at SL and 75 marks in 2 hours at HL. Paper 2 is 44% at both levels, but 50 marks in 1 hour 30 minutes at SL against 80 marks in 2 hours 30 minutes at HL.

Two details there are worth pulling out, because they are the ones most often misreported. First, Paper 1 is not a multiple-choice paper. It is two sections sat together: Paper 1A is multiple choice, and Paper 1B is four data-based questions that are syllabus related and address all themes. At Higher Level, Paper 1A is 40 marks of the 75, which is 40 ÷ 75 = 53.3% of the paper, leaving 35 marks in data analysis. At Standard Level the split is 30 of 55, or 54.5%, leaving 25 marks on Paper 1B. Just under half of Paper 1, at either level, is data work rather than recall.

Second, a calculator is required for Paper 1A. The specimen cover states it in the same breath as the mark total. On the previous course the multiple-choice paper was sat without one, so this is a change of habit as much as of equipment: a student who arrives expecting arithmetic they can do in their head has misread the section, which is written on the assumption that a calculator is on the desk.

It is also worth saying plainly where the secondary sources disagree with the IB. The best-informed specialist page on this search result publishes Higher Level Paper 1 as 70 marks. The guide's assessment outline and the cover of the IB's own Higher Level specimen paper both give 75, with the cover stating the maximum for paper 1A and paper 1B together as 75 marks. Where a summary and the awarding body disagree, the awarding body wins, and a student revising to a 70-mark target is calibrating their timing against a paper that does not exist.

Why does the 44% paper decide the grade?

Paper 2 is the single largest component of IB Biology at both levels, and by a clear margin. At 44% it is 8 percentage points larger than Paper 1 at 36%, and more than twice the internal assessment at 20%, since 44 ÷ 20 = 2.2. At Higher Level it is also the longest sitting in the subject: 80 marks across 2 hours 30 minutes. At Standard Level it is 50 marks across 1 hour 30 minutes. If a family is going to buy tutoring for one thing, the published weightings say it should be this paper.

The paper has two sections. Section A is data-based and short-answer. Section B is extended response, and this is where the choice architecture starts to bite. Higher Level candidates answer two of the three extended-response questions offered. Standard Level candidates answer one of two. That sounds like a small difference and it is not. A Higher Level student needs two questions they can carry to full length under time pressure, out of a set of three, which makes the familiar strategy of revising selectively and hoping the right topic comes up substantially riskier at HL than at SL.

Choosing badly costs more than writing badly. The commonest failure pattern is a candidate who starts an extended response because the opening line looks familiar, discovers three marks in that the rest of the question sits in material they skipped, and has already spent the time. The fix is not another pass through the content. It is a deliberate reading protocol before the pen moves, including reading every extended-response option to the end, and it is a coachable habit that is usually worth more marks than the equivalent hours of revision.

The extended responses also reward structure in a way the data-based questions do not. Section A questions are largely self-scaffolding: the stimulus tells the candidate where to look. Section B does not. Students who came through GCSE biology mark schemes, where a correct point earns a mark and the order rarely matters, tend to produce a list of true statements that never becomes an argument. That is a writing problem wearing a biology costume, and it is one of the few places where a well-chosen hour of tutoring reliably shows up in a grade.

How is the scientific investigation marked?

The internal assessment has a name now, and using the name matters because it signals what changed. It is the scientific investigation: an independent piece of research, timetabled at 10 hours, worth 20% of the subject grade, and identical in structure at Standard and Higher Level. The outcome is a written report, and the report is what is marked.

Four criteria, 6 marks each, 24 in total, a quarter of the internal assessment apiece. There is no personal engagement criterion and no communication criterion; both belonged to the previous course. Each criterion is marked in bands rather than against numbered levels, so any coaching phrased as moving a student "up a level" is describing a scale that is not in use. The practical consequence is that the four criteria are worth exactly the same, which is not how students instinctively allocate their effort.

The report is capped at 3,000 words. That cap is generous in one respect and narrow in another: charts, data tables, calculations, citations and the bibliography are excluded from the count, so the limit applies to argument rather than to evidence. Students who spend their allowance narrating the method in prose and then run short on Evaluation are giving away a criterion worth 6 marks in order to protect one that does not exist. Where the word count is tight, the tables should be doing the work.

Collaboration is permitted and tightly bounded. Where a school facilitates it, the groups formed must be no larger than three students, and every student still produces an individual report on their own research question. The permission covers shared apparatus and shared data collection, not a shared write-up. That boundary is where most academic-integrity trouble on this component begins, usually with a group that drifted from sharing a centrifuge to sharing a conclusion.

The single biggest source of bad guidance on this component is the task it replaced. The previous internal assessment was an individual investigation with a write-up of 6 to 12 pages, also 10 hours and also 20%. Any advice that sets a page target, mentions personal engagement, or lists five criteria is aimed at that older task. This is not a difference of emphasis. The marks are allocated to different things, and a report written to the old shape can be careful, honest, well-presented work and still be marked against something it was never trying to do.

The collaborative sciences project: 10 hours nobody else mentions

The 150 and 240 recommended hours are not all syllabus. The guide splits each course into syllabus content and a separate experimental programme, and the experimental programme is itself divided three ways: practical work, the collaborative sciences project, and the scientific investigation.

The experimental programme is 40 hours of the 150 at Standard Level, or 26.7% of the course, and 60 of the 240 at Higher Level, which is exactly 25%. So roughly a quarter of IB Biology, at either level, is not taught content at all. Families comparing the Diploma against three A-levels often miss this: the hours are published, and a meaningful block of them is laboratory and project time that produces no examination marks directly.

Inside that block sits the collaborative sciences project: 10 hours at both levels, compulsory, interdisciplinary, and not separately assessed. The IB describes the course as culminating in it alongside the scientific investigation — an interdisciplinary project addressing real-world problems that can be explored across the range of subjects in the sciences group. It is the successor to the old group 4 project, and it is the part of the current course that the published tutoring advice ignores most completely.

Because it carries no marks of its own, it is the first thing a stressed student wants to drop and the first thing a tutor who has not read the current guide will let them drop. That is a mistake on timing grounds alone: 10 of the 40 experimental hours at Standard Level is 25% of the block, and 10 of the 60 at Higher Level is 16.7%. Those hours sit in the school calendar whether or not the student engages with them, and a student who disengages still loses the time. Not one of the nine competitor pages we could read on this search result mentions the project at all, which is a fair indication of how much published tutoring copy is written from a list of topic headings rather than from the guide.

Higher or Standard Level: where do the extra 90 hours go?

Every tutoring page on this subject says Higher Level is deeper. The guide says where, theme by theme, and that turns a vague warning into a decision a family can actually make.

Higher Level is 240 recommended hours against Standard Level's 150, a difference of 90. Seventy of those 90 are syllabus content, taking the content total from 110 hours to 180. The other 20 are practical work, which doubles from 20 hours to 40. The collaborative sciences project and the scientific investigation are 10 hours each at both levels, so nothing in the research element expands: a Higher Level student writes the same investigation, to the same 24-mark criteria, in the same timetabled 10 hours as a Standard Level student.

The content expansion is not spread evenly. Theme D, Continuity and change, grows from 34 hours to 60, an increase of 26 — more than a third of the whole 70-hour content difference on its own. Theme C adds 17, Theme A adds 14 and Theme B adds 13, and 26 + 17 + 14 + 13 = 70. In plain terms, choosing Higher Level is disproportionately a decision to spend more time on continuity and change: genetics, inheritance, evolution and the material around them.

That is a more useful answer to "should we take HL?" than any general statement about ability. If a student is comfortable with cell structure and physiology but slow with genetics, Higher Level does not distribute the extra load across their strengths. It concentrates it precisely where they are weakest. The examinations follow the same logic: Higher Level Paper 1 is 75 marks against 55, and Higher Level Paper 2 is 80 against 50, with a Section B that demands two extended responses instead of one.

How hard is IB Biology, on the published numbers?

The question behind most searches for an IB Biology tutor is not "what is on the syllabus". It is "how hard is this, really". The IB answers it twice a year in its statistical bulletin, and not one tutoring page on this search result cites it. Here is the May 2026 provisional bulletin, with Physics at Higher Level included as a comparison from the same session.

Biology at Higher Level returned a mean grade of 4.5 across 33,585 candidates. 7.4% were awarded a grade 7, and 17.2 + 7.4 = 24.6% were awarded a 6 or a 7, so roughly one candidate in four finished in the top two grades. At the other end, 1.7 + 0.9 + 5.1 + 19.5 = 27.2% finished at grade 3, below it, or with no grade at all. Those two figures are close enough to each other that the subject is best described as a wide distribution rather than a hard one.

Standard Level is not the softer landing that families often assume. Its mean was 4.3, with 5.5% at grade 7 and 15.3 + 5.5 = 20.8% at 6 or 7, while 2.8 + 1.7 + 8.0 + 18.9 = 31.4% finished at grade 3 or below including no grade. Both the top and the bottom of the SL distribution are worse than HL's. That is not evidence that SL is a harder course. It is evidence that the two levels are chosen by different students, which is exactly why moving a struggling child from HL to SL is a scheduling decision rather than a grade strategy.

The comparison that reframes the whole question is Physics at Higher Level in the same session: a mean of 5.0 across 19,035 candidates, with 20.5% at grade 7 and 18.9 + 20.5 = 39.4% at 6 or 7. Physics awarded top grades to 20.5 ÷ 7.4 = 2.8 times the share Biology did. Be careful what you take from that. Nothing in the bulletin says Physics is easier or Biology is harder; it says the two subjects are chosen by different populations and grade to different distributions. What it does flatly undercut is the staffroom belief that Biology is the soft science of the group. On the published numbers it is the one that awards fewest 7s of the two.

For scale, the whole May 2026 Diploma Programme cohort was 209,607 students, with a pass rate of 82.6%, a mean subject grade of 4.9 and a mean total of 30.8 points. Biology Higher Level's 4.5 sits 0.4 below that all-subject mean, which is the honest context for a student whose predicted grades hinge on it: Biology is pulling the average down slightly, not carrying it.

Year on year the picture is stable rather than volatile. Higher Level rose from a mean of 4.4 to 4.5 and its grade 7 share from 7.0% to 7.4%, an increase of 0.4 percentage points. Standard Level rose from 4.2 to 4.3 while its grade 7 share slipped from 5.7% to 5.5%. Entries barely moved: 33,585 against 33,079 is 506 more Higher Level candidates, and 22,064 against 21,921 is 143 more at Standard Level. Two sessions is not a trend, and both bulletins carry the word provisional, with final versions published later. Read all of this as the current published picture, not as a forecast of what your child's session will do.

IB Biology in the UK, and why the specialist pool is thin

5,108 students in the United Kingdom sat the May 2026 session, up from 5,064 in May 2025, an increase of 44. Those are whole-Diploma figures, not Biology figures. The bulletin publishes candidate counts by country for the entire programme and subject entries worldwide, and it never crosses the two. We are not going to multiply one by the other and present the result as a UK Biology entry. That number is not published, and inventing it is precisely the kind of thing this page exists to correct.

What the figure does support is a claim about supply. The UK Diploma cohort is roughly five thousand students across every subject in the programme. Only a share of them take Biology, and only a share of those take it at Higher Level. Set that against the size of the A-level market and the conclusion is unavoidable: the number of UK teachers who have taken a class through the current scientific investigation, submitted it, and seen it come back through moderation is small, and it is not concentrated in any one town.

That is the practical case for looking past "a biology tutor who also does IB". The content overlap between IB Biology and A-level biology is real and substantial, and a strong subject teacher will handle the science comfortably. The assessment does not overlap at all. The mark totals differ, the paper structures differ, Paper 1 mixes multiple choice with data analysis in a way no A-level paper does, and the internal assessment has no A-level equivalent in either format or weighting. A tutor who has not worked to the four criteria is guessing at 20% of the grade.

If the choice between the Diploma and A-levels is still open in your household, or you are weighing schools that offer each, our pages on sixth form entry and A-level tuition cover the other half of that decision, including how the two systems present to universities.

What changes next: timetables and on-screen examinations

The November 2026 session timetables the two Biology papers on consecutive days. The Higher Level entry reads "Biology HL paper 1 (1a and 1b) 2h" and sits in an afternoon session, with Paper 2 the following morning. That ordering has a practical consequence for the final week of revision: the longer, heavier-weighted paper falls on the second day, so a plan that peaks on day one leaves the 44% component to be sat on a tired brain.

The larger change coming is the move to on-screen examinations. The IB is running paper and digital examinations in parallel and has released specimen digital papers to schools through its resource centre. The organisation frames the transition as serving a community of more than 180,000 Diploma and Career-related Programme students across more than 5,500 schools in more than 160 countries. For a Biology candidate the component most exposed is Paper 1B: four data-based questions where interrogating a graph or a table on a screen is a different physical act from annotating it in pen, and where the habit of scribbling on the stimulus has to be rebuilt.

The IB has not yet published a May 2027 examination schedule. Where a tutoring page gives you dates for a session that has not been timetabled, it is guessing, and we would rather leave a gap than fill it. We will add the dates here when the IB publishes them.

The other item on the diary is the bulletin itself. Both sessions cited on this page are provisional, and the IB releases final versions afterwards. When the final May 2026 bulletin appears, the figures may move slightly. We will re-read them and update this page rather than leave provisional numbers standing under a fresher date.

How we teach IB Biology

Our IB Biology tutoring starts with a diagnosis rather than a syllabus sweep, because the three assessed components fail in different ways and the remedy for each is different. A student losing marks on Paper 1B has a data-handling problem, and more content revision will not touch it. A student losing marks on Paper 2 Section B usually has a structure problem wearing the costume of a knowledge problem. A student whose scientific investigation is drifting has a research-design problem, and that one comes with a deadline attached and a shrinking window in which to fix it.

We work with specialist tutors, including tutors who studied at Oxford and Cambridge, who have taught the guide first assessed in 2025 rather than the course it replaced. That distinction is doing real work here rather than decorating a page. The gap between the two internal assessment tasks is not a matter of emphasis: a tutor who prepares a student against five criteria and a page count will produce a careful report that is then marked against four criteria and a word cap, and the student will never know why the mark came back where it did.

Sessions run online, which for a cohort this size is not a compromise but the only realistic way to match a student to someone who has actually marked the current task. You can see the full range of what we teach on our subjects page, and students preparing for university entrance testing alongside the Diploma can look at our admissions test preparation.

The first step is a conversation about where the marks are going, not a package. Book a consultation, send us a recent paper or a draft investigation, and we will tell you what we can see in it before recommending anyone.

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