The International Baccalaureate Diploma is not an easy course. However, it can be made easier by choosing the best combination of subjects based on their difficulty and your strengths.

There are four main factors influencing IB subject choices:

1. Quality of tuition available

2. Importance for future career

3. Personal strengths and preferences

4. Difficulty

Obviously, the ideal subject choice is one that has the best teachers available, is in line with the student’s future career choices and interests, and one where a 7 is achievable.

The IB aim to make subjects within groups equally challenging and vary the cut-offs accordingly. However, statistical trends suggest that this process is imperfect and there is a degree of variation regarding difficulty of subjects.

For the purposes of this discussion, the “difficulty” of a subject will be gauged by how likely it is to achieve a 7 in the subject.

Our analysis will focus on the percentage of students who achieved 7 in particular subjects as well as discussion on grade boundaries. Overall, it is important to note that this is just one methodology of analysing subject difficulty. For instance, it may be that a higher percentage of students receive 7s in Chemistry rather than Biology.However, this statistic may be distorted by the fact that students stronger in the sciences tend to choose Chemistry over Biology.

That is not to say that the statistical data is irrelevant. Over a large sample of students, we would expect that subjects of equal difficulty, on average, should have similar percentages of students who receive 7s. Therefore, subjects with an unexpectedly higher proportion of subjects may indeed be “easier”.

Below is an analysis of subject difficulties based on the **IB November 2011 Statistical Bulletin.**

**Group 1 – Language A1**

For many students, there is little choice regarding which language A to choose as they are only fluent in one language. However, for those who are bilingual and attend international schools, there may be an option. Shown below are the percentages of each score out of 7 and the mean grade achieved for each subject.

The greatest sample size is with English A1 and Spanish A1, given Australia and South America are the main countries taking the November exam. One thing is clear – either Spanish A1 students have, on average, weaker language ability, or Spanish A1 is significantly more difficult than English A1.

**Group 2 – Language B and A2**

Group 2 has a much wider variety of languages to choose from.

At first, it would appear that Mandarin B SL and HL have the highest percentage of students scoring 7s. This can be misleading as there are a large proportion of students from Chinese background families that are born in Australia taking Mandarin B. Next we have Spanish B, although the results of this may be skewed by students in South America taking the exam. That said, less than 8% of students in Standard Level achieved less than a 6 and only 4% achieved less than a 6 in HL. Nonetheless, 63% of students taking Spanish B SL achieved a 6 or a 7. French B appears to be more difficult, with the mean grade at 5.41 for SL and 5.35 for HL. One key reason for this is the lack of French background students and families in the Southern Hemisphere. However, comparing this to German B SL, the mean grade is 4.96.

What does this suggest? If you are of Chinese or Spanish background, choose Mandarin or Spanish B respectively. When deciding between French or German, it appears that French students, at SL achieve higher grades than German students at SL. In the southern hemisphere, this is not skewed by family background bias.

** Group 3 – Individuals and Societies**

We can gauge a few key trends from the above table:

- Economics appears to be the easiest subject to get a 7 in. It has the highest proportion of students achieving 7s in SL and HL and has a particularly high mean grade.
- History, the other popular option, appears to be much more difficult, with only 4% achieving 7s at SL and only 7% achieving 7s at HL.
- Philosophy has a high mean grade, but a very low percentage of students scoring 7s, suggesting that it may be easier to receive a decent mark, but significantly harder to achieve an excellent mark.
- ITGS also has a very low percentage of students scoring 7s.
- Business and management has a fairly even spread of students achieving 4s, 5s and 6s, but with a much smaller percentage of students achieving 7s.

In Group 3 at least, one thing is clear. The grade boundaries do not smooth out the bell curve.

** Group 4 – Experimental Sciences**

Group 4 is often controversial regarding difficulty of subjects.

At a glance, it appears that Design Technology has the lowest percentage of students scoring 7s. It is difficult however, to say that it is the most difficult, because of the drastically smaller number of students taking the subject. Furthermore, it may be a subject chosen by students less competent at the sciences.

Biology, Chemistry and Physics however, have a much greater number of students. Looking at the table:

- Physics is the easiest subject to score a 7 in, with 23% scoring 7s at SL and 30% scoring 7s at HL.
- Chemistry is in the middle, with 14% achieving a 7 at SL and 26% achieving a 7 at HL.
- Contrary to popular belief, Biology is not the easiest of the three. A tiny 3% of students receive 7s at SL and a low 11% of students achieve 7s at HL
- The mean grades also support the difficulty ranking illustrated above

Conceptually, Physics may be difficult, however, it has a significantly grade boundaries than Chemistry and Biology. Although Biology may have less problem solving, there is a substantially greater amount of raw memorisation that is required and the IB like to assess students on the minute details. Chemistry may be easier conceptually than Physics, but it has a higher grade boundary to compensate

A note on SL vs HL: The sciences are notorious for having the greatest leap in difficulty between SL and HL. Students who choose HL in the sciences are typically fairly strong at mathematical and quantitative skills and thus why there is a higher percentage of 7s in HL vs SL. Students struggling with the sciences should not pick HL based on the above statistics.

** Group 5 – Mathematics**

Before we delve into the statistics, Australian IB Tuition strongly recommends choosing at least Mathematics SL for students wishing to study a Science, Engineering or Commerce subject at University. Furthermore, Mathematics is a prerequisite for many University courses and is an important skill to for any quantitative career.

Mathematics HL is definitely more difficult than Mathematics SL, which is in turn more difficult that Studies. However, it is the case that in general, students weakest at Maths choose studies. Those stronger tend to choose SL and the majority of those choosing HL Maths are very strong at the subject.

Given the small number of Computer Science students, it is difficult to accurately make claims on its difficulty from this alone.

** Group 6 – The Arts**

Students should note that Group 6 subjects are optional and that there is the option to do another subject from the other groups. The most common choice is to choose another Group 4 (Science) subject.

Nonetheless, it is interesting to note that 0 students achieved a 7 in Film SL and very few achieved a 7 in Film HL. Music and theatre appear to have a higher percentage of students achieving 7s.

Extended Essay

Which subject is best to do the extended essay on?

Let’s convert these to a percentage for the number of As and Bs:

**Group 1**: 27.1% achieved an A and 40.3% achieved a B

**Group 2**: 23.8% achieved an A and 20.9% achieved a B

**Group 3**: 14.8% achieved an A and 28.1% achieved a B

**Group 4**: 23.6% achieved an A and 27.0% achieved a B

**Group 5**: 11.8% achieved an A and 27.0% achieved a B

**Group 6**: 27.4% achieved an A and 28.8% achieved a B

The Groups that stand out are Group 3 (Individuals and Societies) and Group 5 (Mathematics). It is also interesting to note that very few students choose to do their extended essays in a Language B (imagine writing 4000 words in a second language) and Mathematics (a very high degree of mathematical ability is required to write a quality essay). Group 6 also has a smaller number of candidates.

The overall verdict – it is probably best to choose Group 1, Group 3 or Group 4.

Overall IB Scores.

We’ve discussed the individual subjects and it would now be interesting to see what percentage of students achieve particular overall scores.

To get above 40 overall, you need to be in the top 10%. To get a 45, you need to be in the top 1.10%

**Group 1 – Language A1**

**Group 2 – Language B and A2**

**Group 3 – Individuals and Societies**

**Group 4 – Experimental Sciences**

**Group 5 – Mathematics**

**Group 6 – The Arts**

**Extended Essay**

**Overall IB Scores**