IAL Unit 1 Biology and Chemistry: A Week-by-Week Revision Plan for January 2027

When are WBI11 and WCH11 in January 2027?

WBI11 is on Friday 8 January 2027 in the afternoon session and WCH11 is on Monday 11 January 2027 in the morning session. Each paper lasts 1 hour 30 minutes, according to Pearson's final January 2027 timetable.

Check the date in your planner against the final version. An earlier provisional timetable had Biology Unit 1 on Thursday 7 January, and that date is still being passed around. Your centre confirms the local start time, so ask them, not a group chat.

Now count backwards. From Monday 16 November you have 53 days to the Biology paper and 56 days to the Chemistry paper, which is exactly eight weeks. There is one weekend between the two papers. That weekend matters, and I will come back to it in the exam-week section.

The 8-week IAL Unit 1 revision plan at a glance

The plan gives four weeks to content and four weeks to past papers, with every Unit 1 topic in both subjects finished by Sunday 13 December. That leaves 26 days before WBI11 and 29 days before WCH11 for nothing but exam practice.

Why finish so early? Because it is very important to get all of Unit 1 Biology and Chemistry out of the way at least three to four weeks before the exam. A student who is still learning haemoglobin in the first week of January has no time left to learn how the paper asks about it.

If you want a version you can tick off week by week, sign up for the free January 2027 revision plan.

How should you split your time between Biology and Chemistry?

Give Biology the larger share of each week, because Unit 1 Biology is heavy on key terms and processes you have to memorise, while Unit 1 Chemistry depends more on understanding. A workable split is four Biology sessions to three Chemistry sessions a week.

The official teaching hours tell you where the weight sits inside each subject. Pearson's Biology scheme of work gives the two Unit 1 topics 40 hours each, so neither half can be skipped. Pearson's Chemistry scheme of work gives formulae, equations and amount of substance 16 of the 60 Unit 1 hours, double the 8 hours for alkenes. That's why stoichiometry comes first in the Chemistry column and why you keep practising calculations in every week that follows.

Less time for Chemistry does not mean reading only. Knowledge alone is not going to be enough in WCH11. You need to apply what you have learned, so every Chemistry session ends with questions, not with notes.

What should you revise in Weeks 1 to 4?

Revise one block of Biology and one block of Chemistry each week, in the order below, and close every block with topical past-paper questions before you move on. The order is the one I teach, and it does not follow the specification page by page.

Biology Unit 1: nine topics in this order

1. Biological molecules: water, carbohydrates, lipids, proteins and enzymes.
2. Biological membranes: membrane structure, gas exchange and transport across membranes.
3. Nucleic acids: DNA and RNA structure, and DNA replication.
4. Protein synthesis: transcription and translation.
5. Genetics: mutations, inheritance, cystic fibrosis and genetic screening.
6. The circulatory system: the heart, the cardiac cycle and blood vessels.
7. Haemoglobin and the transport of oxygen.
8. Blood clotting.
9. Cardiovascular disease: risk factors, diet and treatments. This is the last topic.

Why this order? Because the molecules come back in every later topic. You cannot explain haemoglobin without protein structure, and you cannot explain cystic fibrosis without membranes and protein synthesis. The Biology specification places four core practicals in Unit 1, so revise each one with its topic: the Benedict's and iodine tests and the enzyme rate practical in Week 1, membrane permeability in Week 2, and vitamin C content in Week 4. If you want the full lessons in this order, they are in the AS Biology course.

Chemistry Unit 1: seven topics in this order

1. Stoichiometry.
2. Atomic structure.
3. Electron configuration.
4. Periodic trends.
5. Bonding, all types: ionic, covalent and metallic.
6. Molecular shape.
7. Organic chemistry: alkanes and alkenes, with their mechanisms.

Each topic here is built on the one before it. Electron configuration explains the periodic trends, and the trends explain the bonding. The matching lessons sit in the AS Chemistry course, and the key terms for both subjects are collected in the IAL Biology and Chemistry notes.

Where do students lose marks in Unit 1?

In Biology the marks are lost on command words, and in Chemistry they are lost on missing key terms. I see the same two patterns every series when I check my students' papers.

Let's start with Biology. The main mistake is that students fail to understand what the question is asking for. They treat an "assess" question as if it said "explain", and they ignore the data. In the long "explain" questions that come with a graph or a table, many students jump to the theory and never describe what the data shows. Marks are awarded for describing the data, so describe it first, then explain it. The January 2025 WBI11 examiners' report says the same thing: check the command word, give a reason in every "explain" answer, and use all the information given in tables, graphs and diagrams. The June 2025 WBI11 report shows the opposite error too, with candidates describing a diagram when the question asked them to explain it.

Chemistry is different. Here the loss of marks is in the key terms, and examiners are fussy about them. Writing what you understand about an ionic bond is not enough. You need the phrase "electrostatic force of attraction". In the June 2025 WCH11 examiners' report, the answers on ionic, covalent and metallic bonding each lost marks for leaving out the attraction. The same report notes that most candidates dropped the final mark of a four-mark calculation by not converting cm³ to m³.

One more number. The mean mark on the January 2025 WCH11 paper was 44, on a paper worth 80 marks, and the report asks future candidates to practise drawing molecules in three dimensions. So a memorised list of bonding terms and shapes is worth real marks in January.

When should you start full past papers?

Start full past papers on Monday 14 December, as soon as the content is finished, and keep solving them until exam week. Ideally you solve as many as possible, and all the Unit 1 past papers with mark schemes and examiner reports from the current specification are in one place.

The research supports this. A review of ten study techniques, summarised by the Association for Psychological Science, gave the highest rating to only two of them: practice testing and spreading your study over time. Rereading and highlighting were rated low. Four weeks of papers, spread across December and January, gives you both of the techniques that work.

Solving is half of the job. In my classes I solve many of these papers along with the students, then they solve on their own and I check over their work. During the winter break the live classes stop for only three days around New Year and return on 2 January. Meanwhile you keep solving papers and submitting them, and I keep checking them.

Does it work? Last year's results were outstanding. The committed students, the ones who were not too busy with too many exams in the same session, came out with a whole set of As and Bs.

What should you do in exam week, 4 to 11 January?

Spend Monday to Thursday on your error patterns in both subjects, sit Biology on Friday afternoon, then give the whole weekend to Chemistry. No new content this week.

These last few days are for going over your mistakes. Open the error log, find the pattern of errors you keep committing, and work on those so you avoid them in the real exam. For one student it is the command word. For another it is the unit conversion. Three patterns per subject is enough.

1. Monday 4 to Thursday 7 January: Biology first each day, Chemistry second. Redo the questions you got wrong, not new papers.
2. Friday 8 January: a light morning with your Biology key terms, then WBI11 in the afternoon. Rest in the evening.
3. Saturday 9 January: one timed Chemistry paper, marked the same day.
4. Sunday 10 January: bonding key terms, molecular shapes and calculation layout only. Minor revision, then sleep.
5. Monday 11 January: WCH11 in the morning.

What if you only have 6 weeks or less?

With six weeks or fewer, cut the topical questions, cover the content through video lessons and notes, and go straight to full papers. Six weeks before WCH11 is Monday 30 November, so anyone starting after that date is on the fast track.

For late starters I recommend the video course, because you can watch specific parts of each lesson. The player has a feature that plays the highlights, the most important parts, so you are not sitting through every minute. Once the videos and the notes are done, you move to full exams and build your exam skills there.

The Unit 1 revision courses for Biology and Chemistry are available together as a $150 package. To ask about it, message us on WhatsApp at +965 5137 5709 or email [email protected].

I hope that this was helpful and I wish you all best of luck in your exam.

Frequently asked questions

When is the IAL Biology Unit 1 exam in January 2027?

WBI11 is on Friday 8 January 2027 in the afternoon session and lasts 1 hour 30 minutes. Chemistry Unit 1 (WCH11) follows on Monday 11 January 2027 in the morning session.

How many weeks do I need to revise IAL Unit 1 Biology and Chemistry?

Eight weeks is comfortable for both units: four weeks of content and four weeks of past papers. With six weeks or fewer, drop the topical questions and go from the lessons straight to full papers.

Should I revise Biology or Chemistry first?

Revise both every week, with Biology taking four sessions to Chemistry's three because it carries more memorisation. In exam week Biology comes first until Friday 8 January, then the weekend belongs to Chemistry.

How many past papers should I solve for WBI11 and WCH11?

Solve as many as you can in the four weeks from 14 December, under timed conditions. Marking each paper and logging your repeated errors matters more than the count.