Introduction

There are four options and students must answer questions on one of them in Section B of Paper 3 of the external examination. For most teachers this means teaching just one of the four options to their students - 15 hours for Standard Level and 25 hours for Higher Level. Thus each option has 15 hours of common SL/HL material divided into sub-topics together with an additional 10 hours of material for Higher Level students. If you do the sums you will see that the options constitute 15 of the 110 hours (13.6%) of the theory part of the programme at Standard Level and 25 of the 180 hours (13.9%) of the theory part at Higher Level. This is approximately reflected in the external examination. At Standard Level Paper 3 contains 20 marks for the option out of the total of 35 marks. Since paper 3 counts 20% towards the total final mark this means that the Option is effectively worth 11.4 % of the final mark. At Higher Level the option counts for 30 out of the 45 marks allocated to the paper. Paper 3 at Higher Level counts 24% of towards the total mark so the option contributes 16% towards the final mark.

Common features of the options

All four options contain similar features or strands. This is to help ensure parity among the options and also to provide a balanced overall syllabus. The common strands are:

Quantitative

Analytical

Organic chemistry

Environmental

Each of these four strands will be examined in the questions on each option.

Teaching the options

Most teachers tend to teach the option at the end of the course after they have taught the core (and AHL at Higher Level) although a few tend to integrate the option into the course throughout the two years. A few teachers do not formally teach any of the four options but give their students time to teach themselves the particular one option they wish to study. There is one advantage to this as it means that all the students in the same class do not have to study the same option. However I would strongly recommend not doing this. I have written many of the Paper 3 examinations and acted as Principal Examiner for marking the scripts many times. In the old programme (last exam November 2015) students had to study two options. Schools where the students answered questions from a variety of options almost always did less well than those where all the students answered the same two options. (The exception to this is schools with large numbers of candidates where students had been taught by different teachers in different classes and hence may have covered different options). It appears that this still holds true now that students only have to study one option. A few schools that have more time may actually teach two rather than one of the options to give their students more choice when it comes to the examination. Whilst I cannot see that this disadvantages the students (and they get to learn some more chemistry) I cannot see that it will have any real advantages as far as the examination goes either.

Choosing the option

One of the questions I am asked most when I run workshops is: How do you choose which option to teach? So what is the answer?

Take a look at the photograph of bikers enjoying themselves at the famous Ace Café just outside London, U.K. It may be a little fanciful but we can make connections to all the four options:

Option A: The alloys of iron and aluminium used to construct the motorbikes (A.2), the polymers used to make helmets (A.5) and materials such as kevlar used in protective clothing (A.9) are very much part of Option A : Materials.

Option B: The proteins (B.2), fats (B.3) carbohydrates (B.4) and vitamins (B.5) which are all covered in Option B : Biochemistry can all be found in the food from the cafe eaten by the bikers.

Option C: The energy required to mIB Docs (2) Teamfacture the motorcycles, the fuel rating of the gasoline (petrol) used in the engine, (C.2), the environmental impact of carbon dioxide, particulates and nitrogen oxide emissions (C.5) and the lead-acid storage battery (C.6) all form part of Option C: Energy.

Option D: If they eat too much in the cafe the bikers may need antacids (D.4), they may be stopped by the police and checked that they are not over the alcohol limit (D.9) and if they are involved in an accident they may need morphine (D.3). All these form part of Option D : Medicinal chemistry.

The point is that you can take almost any situation and by being imaginative can make connections with all four of the options. All of the options relate to Chemistry and Society and in a sense there is no need to emphasise ‘Aim 8’ when studying the options as they embody what it concerns. In the past some of the options were more academic (e.g. Option A: Modern analytical chemistry and Option G : Further organic chemistry) whereas others relied more on memory. Now that all four options have the same four strands this is much less true. All of the options have their merits so the simple answer is that it really does not matter which one you teach. Some might claim that Option D (or possibly also Option B) are best for potential medical students but there is no evidence that this is really true. My advice is to go initially with the one you feel most comfortable with teaching and as you become more experienced ‘take a risk’ and teach another that you are less confident about. This will increase your own knowledge and enjoyment of chemistry and give you more examples and anecdotes for when you teach the Core/AHL.

Three facts are worth remembering:

1. Every year some teachers make the claim to the effect that the questions on one (or more) of the options were easier to answer than the questions on the other options. When papers are written considerable care is taken to try to balance the paper and ensure a genuine 50:50 split between Objectives 1 and 2 and Objective 3. When all the papers are marked it is amazing how many students score roughly similar marks on the two options they attempted and there is no hard evidence that it is easier to score higher marks on any one option compared to the others despite the perceptions of teachers.

2. Whichever option you choose to teach, ultimately you have no control over which option each student chooses to answer in the examination. Sadly some students think they know the answers to an option they have not studied but often they give only journalistic answers and score zero marks as there is not enough chemistry in their answer. Yes, a natural source of the greenhouse gas methane (C.5) is cows’ farts, but the answer required to score the marks must involve some mention of the anaerobic decomposition of organic matter. Impress upon your students that they should only answer questions on the option you have taught.

3. The option taken does not appear on the IB Diploma the student receives. This means that universities will know the final grade in chemistry a student receives but unless they ask specifically they will not know which option the student studied.