In 2020, the Mathematics II exam in Andalusia became a ‘trending topic’ on Twitter. For some, the statement, and the possibility of discarding the most difficult options, made it a ‘gift’. For others, on the other hand, the difficulty of the test had “ruined their lives” because it would sink their average grade and leave them without options to study what they really wanted. And it is that the perception of the difficulty of the exams is always something subjective and often also depends on our nerves and our previous preparation.

There are 5 subjects, however, which are shown to be the ‘bones of the Selectivity’, the subjects that obtain the worst average marks. The digital specialized in education UN Portal has collected them in a report.

The 5 subjects that can sink your Selectividad grade are:


Technical drawing

The exam consists of the realization of two drawings. The first, corresponding to block 1 (Plane geometry) and the second to blocks 2 (Dihedral) and 3 (Axonometry). For years, it has been one of the most difficult subjects at PAU. In 2020 the average was 6,4, but in 2017 it plummeted to 4,7.

Electrical engineering

His average grade in 2020 was only 5,1, the worst of the 29 subjects of the Selectivity. Although few students choose this subject, it is clear that the Electrical Engineering grade can sink your average.

Industrial Technology

In 2018 it was one of the subjects with the lowest average grade, only 5,3. But in 2020, it rebounded to 6,7.

Applied mathematics to social sciences

There are 6 questions that only need to be answered 4. You can get a maximum of 2,5 points for each correct answer. The average grade in 2020 was 6,1, but there is consensus that it is one of the most difficult subjects in the PAU’s.

Business Economics

You have to choose 4 exercises from the 6 proposed, which focus on economic and financial information in the company, financial management, strategic management and business project. The 2020 average was 7,09, but in 2018 it stood at just 5,87.

Physics, Geography or History are also subjects with low average marks in Selectividad, so they will require an extra effort to avoid sinking your final grade. If you need help with any of them, at Academia Guiu we are backed by more than 125 years of experience in academic training and we have verified the effectiveness of our private “on demand” classes, conducted by specialized and experienced teachers in each subject. They can be in our academy, at home or private classes 100% online. We know which are the most complex subjects, so you can choose according to your needs: Mathematics, Economics, Macroeconomics, Microeconomics, Calculus, Statistics, Physics, Chemistry, Computer Science, Programming (Java, etc.), History, etc. and also language classes (English, French, German).